Changelog: what changed and when

By Rohit GaurLast updated October 30, 2026Report a mistake

Corrections to calculations and to published numbers are listed here with the date they shipped. Feature work is listed too, so the site has one history rather than two.

30 October 2026 — corrections from a site audit

Corrected

Bigha to square feet said a Haryana karam is 57.157 feet. The government’s list of land units gives 57.157 inches, about 4.76 ft, which is what makes the 9,075 sq ft bigha; the converter’s number was always right. The deed advice also sent every katha to the Bengal chain: it now names Assam’s 2,880 sq ft katha and Bihar’s kattha of about 1,361 sq ft, and calls the Haryana bigha about 37% smaller rather than “a third”.
Five size pages drew a different room from the one they describe: the 100, 200, 400, 800 and 3,000 sq ft pages now draw 10 × 10, 10 × 20, 20 × 20, 20 × 40 and 50 × 60 ft.
Size pages from 600 sq ft priced paint for the whole home as one open room, which understates it two or three times. That line is gone from them.
How big is 300 square feet called the builders’ 312 sq ft main bedroom that of a four-bedroom house; it is the typical new home’s, about 2,900 sq ft.
The space per person study now says its 857 sq ft is an index (the median new home over the average household), not a measurement, and gives the energy survey’s own 782 sq ft per household member beside its 738.
Average bedroom size: the wheelchair-user bedroom row is now judged at the 1,000 mm clear floor its rule asks, not 750 mm.
How to calculate square footage: the rounding example gives its unit and the right loss, 1.62 m².

Changed

Size pages answer in their first line, with the dimensions and square meters, and link to each other as “1,000 sq ft” rather than “1,000 ft²”. The 1,000 sq ft page gives gaj, cents, marla and guntha.
Average house size and the four room pages lost blocks that did not serve them (a whole house floored as one room, tennis courts, parking spaces), and the room pages lead with their number.
The square meter calculator has its own guide: formulas by shape in meters, the centimeter trap, and why a listing’s figure differs from a tape. The two metric pages use the US spelling, meters, and link to each other.
/compare/ and /import/ are kept out of search, like /projects/: they are empty until you bring your own rooms.

11 October 2026 — how to measure the square footage of a house

Corrected

Average house size said the energy survey counts a finished basement that the Census Bureau would leave out. The Census Bureau’s floor area does include finished basements; what the energy survey adds is unfinished basements and heated or cooled attached garages. The sentence now says so.

New

How to measure the square footage of a house: the ANSI Z765 rules Fannie Mae and Freddie Mac require for appraisals, in one table, with four drawings to scale and a whole house worked out (2,674 sq ft above grade, 900 below) by the house calculator’s own engine. Who requires the standard and since when, why listings and appraisals disagree, and how Canada, the UK and Australia measure. Fourteen sources.
The house square footage calculator now:
- takes a flat ceiling under 7 ft (6 ft 4 in is enough under beams, ducts and other obstructions) and reports the room apart, as nonstandard finished area;
- asks how a room is reached: through finished space, only through unfinished space (nonstandard), or only from outside, which it reports on a line of its own as noncontinuous finished area;
- lets rooms brought over from a calculation be moved to their own level, and says that rooms measured inside the walls add up to less than the house measured outside.
Sources for the method: Fannie Mae’s ANSI FAQ and the standard’s free 2020 draft, now named on the methodology page.

8 October 2026 — how big is an acre

New

Guides, a home for written guides, and the first new one: How big is an acre? An acre drawn to scale as a square and as the chain-by-furlong strip, on an NFL field, filled with twelve tennis courts and inside a square mile; what fits in it, squares from ¼ to 100 acres, new-home lot sizes from the Census, and the survey-foot acre. Twelve sources, each checked.
Guides in the footer, and links to the acre guide from the hectares converter, the acreage calculator and the converters hub.
A publication date in the byline of a written guide, with datePublished in its structured data and og:type article.

2 October 2026 — hectares to acres

New

A hectares to acres converter that opens on one hectare: 2.471 acres, with the exact definition beneath it (an acre is 0.40468564224 hectares). It draws the area as a square beside a tennis court, an Olympic pool or a soccer pitch, sizes a plot in metres, and says how big a hectare is: eight Olympic pools, 1.4 FIFA pitches, about 38 tennis courts.
A byline line on pages drafted with an AI assistant, starting with this one: it says so, and that a separate automated check matched each number to the sources listed on the page.
Rohit Gaur’s page links his LinkedIn profile.

Corrected

Rounded figures beside an “=”. The converters hub wrote “1 ft² = 0.092903 m²”, and every converter put “=” between its two boxes and in its lot tool, rounded or not. Each now writes “≈” where the figure shown is rounded: 1 hectare ≈ 2.471054 acres, 15,000 ft² ≈ 0.3444 acres.
The fence note claimed too much. A square needs the least fence of any rectangle, not of any shape — a circle needs less — and the note now says “of all rectangular lots”.

Changed

The methodology page no longer names the code file behind each formula: the files are not public, so the names told a reader nothing.

1 October 2026 — who writes the site

New

Rohit Gaur has a page of his own: what he does here, how the pages are made, and how to reach him. The name in every byline and in the footer now leads there, with his full name.
The about page says how pages are made: drafted with an AI assistant, and held to the same checks before they go live.

Changed

The error page carries no advertising code, as the privacy policy promises: no ad, and no ad tag, ever loads on it.

1 October 2026 — the acres converter, rebuilt

Corrected

A small area was shown as nothing. The converters rounded every answer to four places, so one square foot read as “0 ac”. They now keep about four significant digits: 0.00002296 acres.
A rounded number was written with an equals sign. “1 ft² = 0.00002296 ac” is rounded; the formula now runs both ways from the exact factor (square feet = acres × 43,560, acres = square feet ÷ 43,560), and the one rounded reciprocal on each page says “≈”.

New

The acres converter opens on one acre, not 1,000. It reads fractions the way land is listed (1/3, 2 1/2, ⅔), says when a number is an exact fraction, and shows what a rounded acreage covers: 0.21 acres is anything from 8,930 to 9,365 square feet.
It draws the area to scale, as a square beside a tennis court or an American football field, with the side of that square, the fence around it, and the same area in square metres, hectares and square yards.
A lot tool turns length × width into square feet and acres, and gives a lot’s depth behind its frontage.
Copy link keeps the number in the address, ready to share.

Changed

The converter tables say what they hold: unit names in the headings, a caption with the rounding, and numbers right-aligned to one precision per column. The acres tables list the fractions land is sold in, the side of each as a square, and common lot sizes.
Links between the converters say where they go: “Square feet to square metres”, not “ft² → m²”.

28 September 2026 — report a mistake from any page

New

Every page with a byline has a “Report a mistake” link beside its date. It opens an email to the site with the page already named, so a wrong number can be reported in one step. Corrections are listed on this page, as before.
Six more pages give search engines a picture of what they draw, without words: the kitchen page’s worked kitchen, the room sizes rooms side by side, the line charts of the house size page and the space-per-person study, and the flooring and tile calculators’ layouts of the room they start on. The sitemap now lists each page’s picture too.

Changed

Every page is checked against WCAG 2.2, the current accessibility standard, rather than 2.1. No page needed a change.
Three pages answer their most-asked question first. The paint calculator opens with how far a gallon goes; the roof calculator says what a roofing square is; and square feet to square metres adds where each unit is used in the UK and Australia, with the minimum sizes of new homes in England in both units.

27 September 2026 — every page described for search engines

Changed

Each page now tells search engines what kind of page it is, in the structured data they read: a guide or reference page as an article, with its heading, author and last update; a hub as a collection; the about and contact pages as themselves; the home page as the site, with its other names and its Pinterest profile. Only what the page shows is described — the date is the “Last updated” under the heading, and nothing claims ratings the site does not have.
The space-per-person data names its licence, CC BY 4.0, on the study page and in the data description Google’s Dataset Search reads. It was already on the research page and in the terms.

27 September 2026 — tables that go both ways

New

Every land-unit page has a table the other way round, from square feet to the local unit: gaj from 100 sq ft to 1 lakh, and cent, guntha, bigha and marla for plot sizes as they are advertised in feet. The gaj page also names varg gaj and varg feet, and works out 30 × 40 and 40 × 60 ft plots.
Square feet to square metres lists house sizes: 1,200, 1,800, 2,400 and 3,000 sq ft.
The gravel page answers first what most people ask: how many tons a cubic yard is — your supplier’s figure if you have one, and about 1.6 tons loose without it.

Changed

The embed code’s link is nofollow, as Google asks of links that come with a widget. Code copied before today still works as it is.

26 September 2026 — our own analytics, and Google’s ad review

New

Google AdSense’s tag loads while Google reviews the site. No ads are shown yet. The tag carries Google’s consent message for the EU, the UK and Switzerland, and it loads only where the privacy policy’s rules allow: never in Quebec, Brazil and Türkiye before you say yes, and not at all where the site cannot tell where you are. ads.txt now names the site’s AdSense account, and the privacy policy says the tag is running.
Umami analytics runs, on a server of our own in India, at stats.sqftmath.com. It sets no cookies and keeps no IP address; your address only makes a visit identifier that changes every day, and the country comes from Cloudflare. It loads only where the privacy policy’s rules allow — after you say yes in Quebec, Brazil and Türkiye, not at all where the site cannot tell where you are — and never for a browser that sends Do Not Track. It never sees a calculation: nothing after ? or # in an address is sent. Its data is deleted after 25 months. The privacy policy, which said it was not running yet, now says it is.

25 September 2026 — numbers read the way they are typed, and pages that fit a phone

Corrections

“1,200” was read as 1.2 on eleven pages: mulch, gravel, topsoil, sod, cubic yard, pavers, concrete, deck, roof, siding and insulation. A 1,200 sq ft bed came out as 0.01 cubic yards. They now read a number the way the calculator always has: 1,200 is twelve hundred and 12,5 is twelve and a half.
Typing 1.5 into the paint calculator’s coats gave 51 coats. Coats and primer coats are now whole numbers in a range, and anything else is refused where it is typed, with the reason.
The house calculator could change an area while it was being edited: taking the last digit off 1,100 left 1.1. Switching it between square feet and square metres also relabelled the numbers instead of converting them, so 2,200 sq ft became 2,200 m². Both are fixed.
The floor plan editor and the tracer read a long wall’s comma as a decimal point: a wall of 1,219.2 cm edited to 1,250 became 1.25 cm. Walls are now shown without grouping, read the way a tape is written (12’6”, 3.5 m), and a length that cannot be used says why.
In field mode, Enter could put a reading into the next room’s name instead of its width. Enter now moves between measurements only.
The wallpaper calculator’s “paper that does not end up on the wall” was a share of the wall; it is now a share of the paper bought, which is what it says.
Switching units and back could change what was typed, by the rounding of a rounding: a paver 2.375 in thick came back 2.374 in, a 9 ft wall 8.999 ft. Switching straight back now gives back the numbers typed, on the paver, siding, concrete and roof pages and for plank sizes. The siding page’s own piece size now converts with the rest, rather than keeping its number under the new unit.
A spreadsheet row with a side of 0 was marked ready to import, and the calculator then refused it. It is now held back with the reason.
The compare page could show the last comparison’s numbers under the new one’s unit while it worked the new one out. The unit now travels with the numbers.

Fixed

A box that cannot be read now says so under itself on the garden and building pages, the quote checker and the converters, where it used to count as nothing without a word; “-5” says it is below zero rather than unreadable. A 0 typed into a product size — a box’s coverage, a tile, a roll — is refused where it is typed.
An emptied length says a measurement is missing, and a total with no room it can count says what to fix, not “Add a room”.
The converters show no answer beside a box they cannot read, and the bigha, gaj, marla, cent and guntha converters keep the figure and the region in their link, so a reload keeps them.
The measurement margin shows its choice again after a reload or a shared link; it came back blank beside the range it had worked out.
The concrete page keeps a pour’s sizes when its kind is changed and changed back, and the garden, cubic yard and concrete pages keep the bag chosen in each unit.
On sixteen pages the calculator now comes straight under its title, as it does on the flooring page: on a phone it started one to two screens down, below the article.
Tables of four columns or more stack on a phone, each row under its first cell with every value named, where they used to hide their numbers off the right of the screen — the room-size tables worst of all.
The charts have a drawing for a phone, with bigger type and fewer years; the last year and the end of a line’s name no longer run off the edge at any width.
An object that does not fit the shape of an area is drawn over it, to scale and saying so, where the drawing was an empty frame.
Form fields have an outline you can see: 3.3:1 against the page, where it was 1.3:1. The tile layout draws its whole tiles, and a file picker looks like a button.
“More tools” is grouped into four sets of tiles and leaves out the page it is on, and every page lists its sources the same way.

25 September 2026 — the header, the footer and the pages about the site

New

A byline under the heading of every page but the calculator itself: who wrote it, linking to the about page, beside the date it last changed.

Fixed

The footer sorts its links into three groups — the site, privacy and terms, help and contact — under the site’s name, with the year and who maintains it at the bottom. The email address on the site’s pages can now be tapped to write to it.
The links to other sizes, rooms and converters no longer run into each other. On a phone each row of them sat over the next; they are now tiles of one size, in columns — three on a phone, six on a wider screen — with the same space between them every way.
The accessibility statement said the site had no motion. The phone menu fades in and the acreage map animates its zooms; both now stay still when your device asks for reduced motion, and the statement says so. It no longer calls its outstanding tests “scheduled before launch”.
The privacy policy names the web beacons, IP address and other identifiers Google’s ads may use, and links Google’s page on how it handles advertising data. The about page now names the one thing typed that leaves your browser: an address searched for on the acreage map.
On a phone the header is one row: the name and a Menu button. The links and the light and dark switch open in a panel under it, which a tap outside or Escape closes. Until now the five links and the switch wrapped onto three lines at the top of every page.
On a computer whose font is wider than Windows’ — most Linux desktops — the header is one row too. The links used to drop onto a second line under the name; the header now takes the few pixels more it needs. Where the row fits, it is unchanged.

24 September 2026 — address search on the acreage map

New

The acreage map finds a place from its address. Type an address or a place name and pick from the suggestions — Esri’s World Geocoding service, nearest to where the map is looking first. Coordinates, map links and Plus Codes are still read in your browser and sent nowhere; the privacy policy says what goes to Esri.

Fixed

The map’s Esri key now works only from sqftmath.com, as Esri advises for a key that is part of a web page, so another site cannot spend the map’s free allowance of searches.

24 September 2026 — the acreage calculator: land measured on a satellite map

New

The acreage calculator measures land drawn on a satellite map, in acres, hectares, square feet, square metres and square yards. Every side is a geodesic on the WGS84 ellipsoid and the area is GeographicLib’s, so the answer is the ground’s and not the flat map’s, which overstates land by about 30% in Delhi and more than two and a half times in London; the page shows that difference for the land drawn.
Several pieces of land, and cut-outs — a pond, a house plot, a road — added up and taken off. Overlapping land and cut-outs that cannot count are reported rather than quietly changing the total, and a corner snaps to a neighbouring field’s so two fields can share a fence. Every side has its length and its direction as a deed writes it, and a margin on each corner turns the answer into the range it really is.
Finding the place takes coordinates in any common form, a Google Maps, Apple Maps or OpenStreetMap link, or a Plus Code — a short one too, once the map is near its town. My location goes to where you stand, and walking the boundary with a phone adds each corner from five seconds of readings, averaged.
Corners can be typed or pasted, and shapes opened or saved as KML, KMZ and GeoJSON, for Google Earth, a GIS or a surveyor. The link keeps every shape.
The area goes on to the sod, topsoil, mulch, gravel, paver and roof calculators, and to the acres converter and the gaj, bigha, guntha, cent and marla converters, which now read an area from a link.
Esri’s World Imagery, with road and place names over it, loads only when somebody opens the map, and the privacy policy says what Esri receives. Where the pictures stop — level 18 over much farmland — the map enlarges the finest level there is instead of showing a hole.

24 September 2026 — fixes from an outside audit

Corrections

“12,5” was read as 125 on the English pages. A comma was always taken for a thousands separator there, so a length typed with a decimal comma came out ten times too long, and the total with it. A comma now separates thousands only where it groups them in threes, as in 1,200; one that cannot, as in 12,5 or 1234,5, is read as the decimal point it has to be. The German reading, ready for when the site has German pages, does the same for a full stop, and several separators that fit neither reading are refused rather than guessed.
A total could rest on a field that no longer read. With “abc” in a field, the field showed its error but the total kept the last reading without saying so. Every total and every estimator’s answer now says, while any field cannot be read, that it still uses the last reading.
The square mile printed as 2589988.1103360001 m² on the methodology page, the computer’s own rounding noise after the real digits. Definitions are now printed to the fifteen significant digits a computer actually holds: 2589988.110336.

Fixed

The about page and the terms said the site did not work to a property measurement standard. The whole-house calculator has applied ANSI Z765’s rules since 22 September; both pages now say what it does and what it cannot do, which is take the measurements for you.
Cloudflare’s page-view count ran whatever the consent rules said. Cloudflare was adding it to every page itself, before the site’s own rules could decide. It is now added by the site, like everything else, only where the privacy policy’s rules allow it, and switching analytics off on the cookie settings page now switches it off too.
The site now answers plain HTTP with a permanent redirect to HTTPS, on www as well, where it had answered with the page itself, and with an error on the www address.
The privacy policy described Umami analytics as running. It is not running yet, and the policy now says so, and that it will be updated before it starts.
Every page now answers its address without the final slash with a permanent redirect. Ten did; the rest answered with a temporary one.
Code blocks that scroll sideways on a phone can be reached from the keyboard, as the tables already could. A check at 320 px on every page now keeps it that way.
Page titles say what each page does, within the sixty characters a results page shows; the headings on the pages are unchanged.
Search engines get each page’s last-updated date, in the page’s structured data and in the sitemap, and the space-per-person study describes its data file as a dataset.

24 September 2026 — tile and plank layouts, with a cut list

New

The tile calculator lays the tiles out, room by room: the grid drawn to scale with every cut piece shaded, centred in the room so both walls get the same cut — on a joint or on a tile, whichever leaves the bigger piece — or started from a wall. It counts the whole tiles and the cut pieces, lists every cut with how many come out of one tile, and sets the layout’s count against the order by area, saying so when the order falls short.
A brick bond is laid row by row, each shifted row with its own cuts at both ends. A long tile is offset a third, not a half: Crossville, Florida Tile and MAPEI from 15 in, and ANSI A108.02 over 18 in. The page says whose limit a half-tile offset passes, and names Daltile’s rule when a grid started from a wall leaves a cut under half a tile.
The flooring calculator lays the planks out for a straight lay, to the makers’ own rules for laminate (Shaw), vinyl plank (Lifeproof), floating engineered wood (Kährs) and solid hardwood (the NWFA): the gap at the walls, how far apart end joints must be, the shortest piece and the narrowest row, every one of them editable and kept in the link. Each row starts with an earlier row’s offcut when that keeps the rules, a narrow last row is balanced with the first, and alternate rows are kept from lining up. The cut list gives every row’s width, start and end, and where each piece comes from; the planks it takes are set against the boxes by area.
The layout says when the rules cannot all be kept — end joints 12 in apart on a 22 in plank, or a room whose length leaves a short piece whatever the start — and how close it comes, rather than laying a floor that quietly breaks them.

24 September 2026 — insulation and siding

New

An insulation calculator for an attic, walls or a floor. It starts from ENERGY STAR’s R-value for your climate zone — for an attic with none, or on top of the 3 to 4 inches many already have — and counts the bags Owens Corning’s AttiCat chart or Greenfiber’s Sanctuary Defense card needs for it, with the depth to blow it to, because the chart’s R-value needs both. It gives the weight, the depth markers the code asks for in a blown attic, dense-packed cellulose for walls filled from outside, and batts counted by the framing they sit between.
A siding calculator that measures the way the makers estimate: vinyl counts windows and doors in and takes half of a garage or sliding door off, as the Vinyl Siding Institute and CertainTeed do, then adds their 10 per cent; fiber cement takes every opening off, as James Hardie’s chart does. It counts cartons of double 4 or double 5 inch panels or 12-foot planks at their exposure, the starter strip, J-channel and corner posts in the lengths they are sold in, the house wrap in DuPont’s rolls after their laps, and the nails by weight — and hands the walls to the insulation page, for filling them while the siding is off.
The roof calculator hands the attic under the roof to the insulation page, as the house inside its walls rather than the roof with its overhang.

24 September 2026 — pavers, concrete, the roof and the deck

New

A paver calculator. Pavers counted by the space each takes with its joint, 5 or 10 per cent over as Oregon State advises, and everything under them: ICPI’s base for a patio or a driveway, ordered loose and weighed, the inch of bedding sand, the depth to dig and what comes out of the hole, and the edge restraint round the outside.
A concrete calculator for slabs, footings, walls, post holes, columns and steps, as many pours as the job has, with the 4 to 10 per cent allowance the National Ready Mixed Concrete Association advises. It counts Quikrete’s bags from 40 to 90 lb at their printed yields, Blue Circle’s 20 kg bag in metres, or any bag you give it, and warns when a bagged slab is thinner than the mix is made for. Rooms measured on the calculator arrive as slabs.
A roof square footage calculator that works from the ground: the footprint, the overhang and the pitch give the roof’s area for any shape, and a gable or hip gives its ridge, hips, eaves and rakes too — with bundles from Owens Corning’s coverage, the ridge cap, the starter rolls, the drip edge and the ice barrier, and the building code’s rules for low-pitched roofs.
A deck calculator that counts boards row by row: which rows fit in one board and which are joined over a joist, which board length wastes least, the joists and two screws at every one. It carries Trex’s boards and spans for a US deck and the Timber Decking and Cladding Association’s for a British one, gives the widths that need no board ripped, and sends the footings to the concrete calculator.
The calculator links to pavers, concrete and decking beside the garden pages.

Corrections

A count of a thousand or more lost its thousands separator. Bags on the garden pages and pads, rolls and pallets on the sod page read “1234 bags” rather than “1,234” (and would have read “1234” rather than “1.234” in German). They now print the way every other count on the site does.

23 September 2026 — sod and the cubic yard

New

A sod calculator. The lawn’s area and 5 per cent over it, as Mississippi State advises, in the pieces sod is sold in — pads of 16 × 24 inches, rolls of a square yard, a British roll of a square metre, or any size the grower gives — and in pallets of Tennessee’s 50 square yards, with what the last pallet has spare. It says what the order weighs, at Tennessee’s ton a pallet, and hands the lawn on to the topsoil page at the 6 inches a new lawn wants under it.
A cubic yard calculator for a job that is more than one box: add rectangles, circles, triangles and areas you already know, each at its own depth, and it adds them up with a table of where the volume went. Gravel and topsoil are weighed at the same published figures as their own pages, anything else at the weight you type, and bags are counted in the sizes a garden centre sells. Rooms measured on the calculator arrive as sections of their own.
The calculator offers both, beside mulch, gravel and topsoil.

23 September 2026 — the garden pages fixed, and quotes in any language

Corrections

A metric garden page sold one bag too many when the bags came out exactly. A square metre of mulch 2.5 cm deep is 25 litres — one 25 litre bag — but floating-point arithmetic reached it as 1.0000000000000002 bags, which rounded up to two. Seven other calculators each carried their own guard against exactly this; the garden pages were written without it. Every count on the site now uses the one shared guard.
On a metric garden page, “one bag covers” was a number of square feet labelled square metres — ten times too big — and the coverage line said a cubic yard covers so many square feet at a depth in centimetres. Both now answer in square metres and cubic metres.
A bed measured in metres on the calculator arrived on the gravel and topsoil pages weighed wrongly. The weight field kept the figure for a cubic yard (1.62 tons) under the label for a cubic metre, which should read 1.92 tonnes, so every weight was about 16% light. A weight now remembers the unit it was given in, and only its display follows the page.
Switching a garden page between feet and metres kept the digits — 20 ft became 20 m. It now converts them, the way the calculator always has.
A quote wrote a question mark for any letter outside Western European text: the Ł of Łódź, the ş of a Turkish surname, a name written in Hindi, the rupee sign on every price. They now go into the PDF as your browser draws them, in whatever script they are, with the words kept in the file so a reader can still search for them. The same goes for room names in the projects PDF.
Long lines in a quote ran off the page or into the next column — a paragraph of terms, a long address, a room name. They now wrap, and a quote that runs to a second page repeats its column headings there.
The garden pages said “follow the calculator’s link here” and the calculator had no such link. It now offers mulch, gravel and topsoil for the area it has measured.
A page could throw an error eight seconds after it loaded in a browser that answers the offline copy’s registration with nothing at all, as some privacy tools do. It now checks what it was given. The new check for errors on every page is what found it.
The tests that throw thousands of random rooms at the arithmetic were mostly throwing tiny ones. Drawn from zero up, a random number is far more often 1e-200 than 10, so the four-walled room test had nearly always been handed four corners in one spot. They now draw across the whole range as well, and the arithmetic holds up; one of them, handed walls of 2e-16 beside walls of 1, had been failing now and then on rounding no tape could measure.

New

The garden pages keep a calculation in their link, like every other calculator on the site: a reload keeps it, the link can be copied, printed or carried to a phone with a QR code, and the printout carries the date, the link back and every setting the answer rests on.
Bags a British shop sells. A metric page counts bark and topsoil in the litre bags B&Q sells them in, and gravel by weight — 20 kg bags and 800 kg bulk bags, counted through what the stone weighs. Any other bag size can be typed.
Depths in centimetres too, rounded to what a person would measure: 7.5 cm, 10 cm, 30 cm.
The methodology page has the garden calculators’ arithmetic — volume, compacting, weight and bags — with tables of the weights and depths generated from the calculators’ own code.
The estimators hub is in two halves, floors, trim and walls, and the garden, the path and the drive.
Every page is now checked for errors in the browser console on every build, and the nightly speed check covers the floor plan editor, the tracing page, the house calculator and a garden page as well.

22 September 2026 — gravel and topsoil

New

A gravel calculator. An area and a depth, in cubic yards, bags or tons. The weight is a published figure rather than a guess: Penn State’s road-aggregate handbook orders 0.04 tons a square foot for an 8-inch loose lift, which is 1.62 tons a loose cubic yard, and the weight field takes a supplier’s own figure over it. The depths are Clemson’s inch of stone over a bed, Oregon State’s 4 to 6 inches of base under pavers, and the handbook’s 6 inches finished for a drive.
It knows what compacting takes. The handbook lays 8 inches loose to finish at 6, and PennDOT’s sheet places the same aggregate between 6 and 8 inches uncompacted; tick the box and the calculator orders a third more than the finished volume, and says what a loose yard covers once it is compacted.
A topsoil calculator. The same arithmetic, with Penn State’s 4 to 6 inches (settled) for a new lawn and Maryland’s 8 and 12 inches for raised beds. A mix field shares the volume between topsoil and compost in the 1:2 or 1:1 Maryland gives, and it weighs soil at Penn State’s 1.33 g/cm³ for a dry silt loam — 1.12 tons a cubic yard — and says why a delivered load weighs more.
One form for the garden. Mulch, gravel and topsoil share one form and one result card, so a fix to one is a fix to all three. Nothing on the mulch page changed but the bag sizes on offer, which now start at half a cubic foot.

22 September 2026 — mulch, and the start of the garden

New

A mulch calculator. A bed’s size and the depth you want, in cubic yards or in bags, with what one bag covers at that depth. One cubic yard covers 324 square feet an inch deep, which is where every one of these numbers comes from.
It does not invent a depth. It offers the ones Clemson’s fact sheet and Penn State Extension actually give — 2 inches for fine or matting material, 3 for wood and bark, 4 for coarse nuggets — with what each is for, and says something when a deeper bed is asked for, because mulch piled deep starves roots of oxygen and kills the inner bark. Both sources are on the page with the date they were read.
A bed measured on the calculator comes across in the link, so an odd-shaped border does not have to be measured twice.

Gravel, topsoil, sod and the plain cubic yard run on the same arithmetic and are next.

22 September 2026 — a quote on your own letterhead

New

Make a quote for a client, from the calculator. Your company name, address, logo and terms are saved in this browser; the quote is one line per room, priced at exactly the waste and price the Waste and cost panel is using, with tax and totals — and it downloads as a PDF.
The logo goes into the file as a picture, not a link to one, so the quote opens the same on anybody’s machine. Whatever you upload — PNG, SVG, a photo of a letterhead — is converted to a JPEG on your device and embedded directly.
Nothing is uploaded. The details, the logo and the PDF are all made and kept in your browser.

The quote and the screen can never disagree: every line is built from the same numbers the cost panel shows, and a test proves the two come to the same total to nine decimal places. The money column is aligned on its right edge using the font’s own metrics, which is why the decimal points line up.

22 September 2026 — the whole house, the way an appraisal counts it

New

A house square footage calculator that follows ANSI Z765, the measuring standard Fannie Mae has required for appraisals since 1 April 2022. Levels, finished and unfinished space, ceiling-height rules, openings and the stairs through them, garages out — and the statement an appraisal actually needs, with the declaration the method calls for.
It will not give you one number. Above-grade and below-grade finished area are shown separately and never added, because the standard says no statement of a house’s finished square footage can be made without that distinction. A finished basement is not an upstairs bedroom.
Everything it leaves out is listed with the reason: the part of a sloped room under 5 ft, a room that fails the half-at-7-ft test, a room reached only through unfinished space, the garage.
The rooms come across from the calculator — the link carries them, so nobody types the same house twice into two pages and gets two answers.

On the source. The official copy of ANSI Z765-2021 has not been bought. Every rule was read in Fannie Mae’s Selling Guide and in an Appraisal Institute chapter’s published slides that reproduce the standard’s wording, and the methodology page now lists each rule with where it was read and says plainly what is still unverified.

22 September 2026 — photo notes

New

A photo of the room, with the measurements on it. Every room card now has a Photo notes panel: take a picture with the phone’s camera or choose one, then tap it to put a label where the measurement is — “2.4 m to the alcove”, “door 900”. The labels print with the room.
The photograph stays in this browser. It is read straight off the device into the page, kept in this browser’s own store, and never uploaded. It is not in the share link either; only the labels travel, because they are what the person you send it to needs. The privacy page now lists both of the site’s databases, saved projects included, which it should have done before.
Labels can be placed without dragging: add one from the button and move it with Alt and the arrow keys.

The panel and the picture are fetched only when the panel is opened, so nobody pays for a photo feature they never use.

22 September 2026 — how good is the measurement?

New

A measurement margin, and what it does to the answer. A tape read to the nearest half inch makes a 12 × 12 room anything from 143 to 145 square feet. Say what your measurements are good to — as typed, ±¼ in, ±½ in, ±1 in, or the millimetre equivalents on a metric project — and the total says the range as well as the figure.
The estimators order for the top of it. Flooring, tile, carpet and the paint for a ceiling are worked out for the largest the rooms could be, and the page says which figure it used. Ordering for the middle of a range is ordering too little half the time.
The margin travels in the share link and converts with the unit toggle, because an inch is still an inch after you switch to metres.

The range is exact where the shape has measurements to move: every combination of the extremes is tried rather than assuming the area grows with each one, which it does not — widening the notch of an L-shaped room makes it smaller. A room that was drawn or traced has corners rather than measurements, so its walls are moved instead and the page says “about”.

A typed area — a cutout entered as “24 sq ft” — is taken as given. It is a figure, not a reading, and inventing a margin for it would be making something up.

22 September 2026 — take the drawing with you

New

Save the drawing. Every room in the calculation, drawn to scale with its dimensions, its name and its area, and the total underneath — as an SVG or a PNG. It is drawn again for the file with its own colours and fonts rather than copied off the page, so it opens correctly in anything: a message, a document, a builder’s email. A cutout that was drawn in the floor plan editor appears where it is.
Send it to another app, on a phone or anywhere else the browser can share a file. The button appears only where that works, rather than failing where it does not.
A QR code for the link, so a calculation on a laptop can be picked up by the phone that is going to the site to measure. It is shown as a picture, not as markup handed to the page.

Both the drawing and the QR code are built only when the button is pressed: none of that code is in the page for the people who never press it.

22 September 2026 — trace a room off a photo

New

Trace a floor plan. Open the drawing an agent sent, or a photo of the plan on the wall, mark one thing you know the length of — a printed dimension, a scale bar, a door — and trace the room. The area comes out in feet or metres and opens in the calculator or the editor like any other room.
The image never leaves the browser. It is read straight off the device into the page and shown through an <image> element, never inlined as markup whatever kind of file it is. Nothing is uploaded, stored or sent anywhere, and the test suite proves it: the trace runs with every network request recorded, and there is none.
The scale is one line, and it can be corrected at any time. Corners are kept in the image’s own pixels and converted only to be shown, so changing what the marked line measures moves every number and not one traced corner. A dimension printed on the plan can also be typed into a wall afterwards, which is the quickest way to correct a hand-traced corner.
Walls traced nearly straight are straightened, because a plan photographed by hand never is. A room that really is at an angle keeps its angle — the straightening can be turned off.

Fixed

Corner handles carried tabIndex, and an SVG attribute is case-sensitive where an HTML one is not. The first paint’s markup was lowercased by the HTML parser and worked; every corner the editor drew after that could not be focused at all. Both editors now write tabindex, and a test draws a corner after load and checks it can be reached.

21 September 2026 — the floor plan editor without a mouse

New

Every corner can be reached with the Tab key and moved with the arrow keys — one grid square at a time, or a tenth of one with Shift — and Delete takes one out. Each nudge is its own step to undo. This is the drag alternative WCAG 2.5.7 asks for, in the place somebody tabbing through the page will actually look for it.
Each wall’s direction can be set from the table, beside its length: right, down, left or up. The wall keeps its length and its starting corner and swings the far one round, the same way typing a length slides it along.
A room can be built by typing walls — 14 ft right, 9 ft down, 14 ft left, Close the room — with no drawing at all. The readout counts the wall as it goes.

Fixed

The canvas called itself a picture, which hid everything inside it from a screen reader — corner handles included. It is now a labelled group whose handles are reachable, with the drawing itself marked as decoration.
A room could not be drawn to the left of or above where it was started: the shape engine treated a coordinate as a measurement and refused a negative one. A corner may now sit anywhere on the plane, which is what dragging one up and to the left has always meant.

21 September 2026 — cutouts that know where they are

New

A cutout can be drawn where it actually stands. Until now a staircase was “24 sq ft off the total” and nothing said where it was. In the floor plan editor you can now walk its outline inside the room, and the drawing carries it: the room’s diagram in the calculator and on the printed sheet shows the hole hatched in its place, and the share link carries its corners.
It is checked as you draw it. A cutout may sit flush against a wall — that is where a closet goes, and where a clipping library’s tolerance would invent a sliver of overlap — but it cannot cross one, and two cutouts cannot cover the same floor, because that floor would come off the total twice. Both tests use the same exact predicate that already rejects a room whose walls cross, so the answer does not depend on rounding.
A drawn cutout’s area is read-only in the calculator, and says how many corners it has. Typing a different number would put the drawing and the total at odds; it is changed where it was drawn. Changing the room to a shape that is not a drawing keeps every cutout’s area and drops its position, which no longer means anything.

Fixed

A cutout whose first corner sat exactly on a corner of the room could not be closed: the tap matched the room’s corner instead of its own. Closing now goes by where the corner landed, not by which of two corners in the same place the snap picked.

21 September 2026 — draw the room

New

A floor plan editor. Walk the outline on a grid instead of splitting an odd room into rectangles. Corners land on the grid, on a corner already put down, or on a straight line from the last one, so a plan drawn with a thumb still has walls that meet; come back to the first corner and the room closes. Zoom with the wheel or two fingers, drag to move the plan, undo and redo with the buttons or Ctrl+Z, and start from a rectangle, an L or a T.
The same plan in numbers, underneath. Every wall is a field: type 12 and that wall becomes twelve feet, keeping the direction it was drawn in — the corner at its far end moves and the rest of the room stays where it was. Corners can be removed there too. The editor is therefore usable with no dragging at all, which is what WCAG 2.5.7 asks for, and it is the quicker way to correct a tape reading for everybody else.
A drawn room can be changed again. Until now an outline that arrived from a drawing or a spreadsheet could be costed but never edited — the calculator had no fields for it. Its room card now carries Edit the outline, which opens the drawing with the whole calculation in hand: the other rooms, the prices and the estimator settings all come back with it when you are done.

Fixed

The drawing and the table no longer disagree while a room is still open: the readout counts the wall drawn so far rather than quoting the area of a shape that has not been closed yet.
Wall lengths are written beside their wall rather than on it, where the corner handles used to land on top of the digits.

21 September 2026 — the site goes live

New

A light/dark switch in the header. Three choices, not two: light, dark, or follow my device, which is the one most people want and the one a single toggle takes away from anybody whose phone turns dark at sunset. Your choice is kept in this browser and applied before the page is painted, so moving from page to page never flashes white at somebody reading in the dark. Without JavaScript the switch is not shown at all — a control that cannot work should not be offered — and the site still follows your system setting, as it always has.

21 September 2026 — land units and quotes

New

The land units of South Asia, with the state written on them. A bigha is 14,400 square feet in West Bengal and Assam and 9,075 in the bigha-biswa districts of Haryana; a kattha is 720 square feet in Bengal, 2,880 in Assam and about 1,361 around Patna. So the converters ask which state’s records you are holding before they answer, show the sentence those records define the unit by, and link the document it was read from with the date somebody opened it. Five pages: gaj, cent, guntha, bigha and marla, with kanal, biswa, lessa, chatak, dhur, kani, gonda and kora alongside them, and the Bangladeshi katha, bigha, decimal and kani from the Ministry of Land’s own table. Every value is on the methodology page with its citation.
Three units are deliberately missing, and the pages say so: Rajasthan’s bigha (two jaribs and a single source), Pakistan’s marla (225 square feet in Lahore’s planned schemes against 272.25 on the old records, and no government copy of the rules we could open), and the Tamil Nadu ground of 2,400 square feet, which is quoted everywhere and stated in no document we could find. A land unit is worth more missing than wrong.
Check a quote. Type the area and the total from a contractor’s quote and the calculator compares them with the rooms you measured — not to say whether a price is fair, which is not arithmetic, but to name why two figures differ and give you the question to ask. It knows the four ordinary reasons: a waste allowance (and whether it is the size of one), an area taken before the island and the staircase came off, a quote that is short, and the one that catches everybody — the same room written in another unit, where 13.4 against your 144 is square metres rather than a tiny job. It also shows the rate over their area and over the floor you actually have, which are different numbers.

21 September 2026

New

A room with four walls and not one right angle. Pick Four walls + diagonal and measure one line corner to corner: four wall lengths alone do not fix a room’s area — the same four enclose less floor the more the room leans — and the diagonal does. The room is worked out as the two triangles that diagonal makes, and the page shows each corner’s angle, names the one furthest from 90°, and says what the second diagonal must read before you measure it. Measure it anyway: if the tape disagrees with that number, one of the six is wrong, and the page says so rather than averaging them into a total nobody can check.
Show how this was worked out. The whole calculation, in the order it happens: each room’s formula with the numbers you typed, every cutout taken off by name, every extra area added on, and the running total as each room joins it. It ends on the same figure the top of the page has been showing, worked out the same way, so a total can be checked on site rather than believed.
Field mode. For measuring with a tape or a laser meter in hand: boxes big enough to read at arm’s length, Enter to move to the next measurement with the old one selected so a meter’s reading replaces it, and the screen held awake where the browser allows it. Numbers are read in the fixed format a meter types, so 3.456 from a Leica is three and a bit, whatever the page’s language does with dots and commas. The choice follows you from page to page.
Saved projects. Give a calculation a name and keep it on this device: the list shows how many rooms, how big and when it was saved, and any of them opens back in the calculator exactly as it was left. Projects can be renamed and duplicated, so a second quote can start from the first. Nothing is uploaded and no account is involved — they live in this browser’s own storage, and the page will ask the browser to hold on to them rather than clear them for space.
Every project comes out as a file. CSV for a spreadsheet — one row per room, the sides and the area, the unit in the column titles and a total at the foot. JSON for the whole calculation, which carries the shapes themselves and opens the same rooms again. PDF for the version somebody signs: a room table written by the page itself, not by a three-hundred-kilobyte library, so it costs nothing to anyone who never presses the button.
A backup of the lot, and a way back in. One file holds every saved project. Import it on a new laptop, or after clearing your browsing data, and they are all there; importing the same file twice replaces what it already holds instead of making a second copy of everything. Safari clears a site’s storage after seven days without a visit, which is why the export is on the page rather than in a menu.

Corrections

An imported table’s total row was read as another room. A table pasted from a spreadsheet usually ends with “Total”, and so does the CSV this site exports. Ticking “turn a row that gives only an area into a square” then added that sum as a room of its own and counted the whole floor twice; without the tick it was reported as a row that could not be read. The total is now recognised — in English, and in German for when that goes live — and set aside, and the preview says that is what happened.

20 September 2026

Corrections

Garage and parking sizes on the size pages. The 100 sq ft page called a single parking space about that size; San Diego’s code asks at least 8 × 18 ft (144 sq ft) of one, New York’s 8 ft 6 in × 18 ft. The 200 and 600 sq ft pages said a one-car garage is 200 sq ft “in most of the United States” and a two-car garage “usually 20 × 20 or 24 × 24 feet” — no source says either. They now quote city minimums that were read at the source, and link to the new garage page.
Size pages were missing a paint figure. Each size page gave the cost of flooring the area but not of painting its walls, which the site’s own plan asks for. Both are there now, worked out by the estimators themselves, with the room one click from the calculators.
The formula line in German (not live yet) listed a triangle’s three sides as “2,5, 3, 4” — four numbers or three? Where the comma is the decimal point, listed numbers are now separated by semicolons.
/favicon.ico was missing. Browsers, crawlers and bookmark bars ask for that file by name whatever a page links, and the site had only the SVG and PNG icons. It is now built from the same SVG master in 16, 32 and 48 px.
The size pages linked no converter, which the plan asks of them. Every size and room page now hands its own number to the square feet ↔ square metres converter, and the converter opens on it.
A calculation opened with a price kept its total hidden behind the closed “Waste and cost” panel. The panel now opens when the link carries a price, whether it came from a size page or from somebody sharing a costed calculation.
“Rooms that come to this size” repeated itself. The list searched whole feet first, then half and quarter feet, and counted 20 × 15 ft as a new shape each time it found it again — so the 300 sq ft page offered the same room three times. Each shape is now listed once, which leaves room for the ones that were being crowded out: 300 sq ft also comes as 18¾ × 16, 24 × 12½ and 25 × 12 ft.
The share box could show a fragment instead of a link. For a moment after a calculator page came alive, the box held #v1=… without the address in front of it — long enough to copy something that goes nowhere. The address is now part of the first thing the box draws.

New

Import rooms from a spreadsheet. Paste the rows straight out of Excel, Sheets or Numbers, or choose a CSV: tabs, semicolons, decimal commas, feet and inches, fractions, and a whole size in one cell are all read. The table is read in your browser and nothing is uploaded. A row that gives only an area is listed as such rather than turned into a square, and a row that cannot be read names the cell that stopped it while the rest still imports.
Compare two calculations. Put two rooms, two layouts or two quotes side by side: area, walls, materials and cost, with the difference and the percentage worked out. The second side is converted into the first side’s unit; prices are never converted, so two currencies are shown as they are. Both calculations travel in the page’s own link.
The site installs, and works without a connection. The calculator, the estimators, the converters and the guides are kept on the device, so they open on a site with no signal; a page that was never saved says so instead of failing. Published data and share images are always fetched fresh, never served from the cache.
The calculator, embeddable. Pick the widget, the theme, the starting unit and the size; copy the code; paste it into your own page. The frame carries no ads, no analytics and no cookies, it tells your page how tall it needs to be, and the credit line sits outside it, where a link to this site is worth something to both of us.
Research, and the site’s first study: space per person in American homes. The median new US home gives each occupant 857 sq ft, against 507 in 1973 — two thirds of that from bigger houses, one third from smaller households. It divides two Census series year by year, 1973 to 2025, and shows both.
The data as files. Every series behind the study is published as a CSV, written at build time from the same modules the pages read: space per person, new home size and household size. Free to reuse with attribution.
Room sizes. A hub and four pages — bedroom, kitchen, living room and garage — that set building-code minimums, space standards, builders’ survey figures and rooms measured by surveyors side by side, each with its source.
What a size holds, worked out rather than asserted: the biggest bed a room takes with 750 mm clear round it, the cars a garage takes by a published parking-space rule, the screen a living room suits at 40°, and the width each kitchen layout needs by the NKBA’s guidelines — each drawn to scale by the same function that decides it.
Open this room in the calculator. Every room and size page carries its worked example into the calculator and the estimators, prices included, so they open on the same totals the page quotes.
The measuring guide has a table of typical room sizes.
Six more size pages — 300, 400, 700, 800, 2,000 and 3,000 square feet — each with its own drawing, comparisons, layouts and costs, and each linked to the sizes nearest it.
Average house size: the median new American home every year since 1973 as a chart and as a table, where a size sits among the homes built in 2025, and the same house measured three ways — the Census Bureau’s finished floor space, the energy survey’s household estimate including basements, and the tape English surveyors run inside the walls.
Three more real-life comparisons: a parking space, a pickleball court and a volleyball court, each from the body that sets its size.

19 September 2026

Corrections

Emptying a measurement. Clearing a room’s length or width to retype it made the page stop answering until it was reloaded: the share link could not be written for a room with an empty field. The room now keeps the field empty and asks for a number, and a link or a saved session with an empty field brings the room back instead of dropping it.
Typing fast on a slow phone. A keystroke could be lost and the old number put back — “15” typed over “8” came out “85” — when the browser was slow to draw the next frame. Every number field now decides what the person typed from the page as it is, not from a moment before.
A circle measured by its radius turned into one measured by its diameter when the radius was emptied and typed again, and lost three quarters of its area.
Rooms added in centimetres, inches or yards were 3.6 cm, 12 in or 12 yd across. A new room is now 12 ft or 3.6 m, in whatever unit is chosen.
Switching units on the wallpaper and drywall pages changed the ceiling height from 8 ft to 2.4 m instead of 2.44 m, and with it the number of rolls and sheets.
A wall picked for wallpaper on a three-sided room could move to another side when a side was corrected. Walls are now numbered A, B, C as typed.
Slanted sides shorter than the height of a parallelogram or trapezoid are impossible, and are now refused instead of counting less wall than the room has.
Tin sizes. A comma typed to start a new tin size disappeared at once, and a very large size typed by mistake could stop the page. Where a comma is the decimal point, sizes are now separated by semicolons.
Tile prices. A per-tile price went on costing the job after the field had switched to a box price.
Wallpaper for a room with no height was quietly left out; it now says the height is missing, as the paint and drywall pages do.
Dark theme. The Copy link button and every error message fell short of the contrast the accessibility standard asks for.
Printing an estimate printed the whole page — every field, button and paragraph, five or six sheets. It now prints the answer, the settings it rests on and the rooms, with the date and the link back.
Tables on a phone fitted the screen by breaking words and numbers anywhere — “Roo” and “m”, “13.” and “5” — even on phones with room for them. Words now stay whole; on a screen too narrow for a table, the table scrolls sideways in its own box and the page stays put.
Baseboard for shapes without measured sides. A triangle given by base and height, and a trapezoid or parallelogram without its slanted sides, are drawn at a readable angle — and the baseboard page measured that drawing, so a 12 × 10 ft triangle came to 35.3 ft of trim that nobody had measured. Those rooms now count as having no known walls, as they already did on the paint page. A trapezoid with both slanted sides uses them as typed; before, its drawing’s equal sides were used instead, 30.25 ft of trim for a room whose perimeter is 31.
Room ceiling height. The field was labelled twice on the paint and baseboard pages.
Coats field. On a wide screen the paint page’s coats box stretched to one and a half times its height, to match the hint beside it.
Published rounding rules. The methodology page now states how the estimators round: whole units always up after the waste, paint to the quart or into your tin sizes, and roll goods by their cuts. They always worked that way; the page did not say so.

New

Privacy choices that follow the law where you are. Google’s certified consent message in the EU, the UK and Switzerland; the site’s own opt-in panel — in English, French, Portuguese and Turkish, with “Accept all” and “Reject all” side by side — in Quebec, Brazil and Türkiye; an opt-out everywhere else, where a browser’s Global Privacy Control signal counts as one. Nothing that measures anyone loads before these rules allow it, and for now nothing loads at all: no analytics or advertising is switched on yet.
The cookie settings page, and a “Do Not Sell or Share My Personal Information” link in every page’s footer.
The privacy policy, rewritten for analytics and advertising before either is switched on: what each service receives, where it is kept, for how long, and how to say no.
The wallpaper calculator. It counts drops the way a manufacturer’s calculator does — each drop rounded up to whole pattern repeats, then how many a roll really gives — so a 53 cm straight match in a 4 × 3 m room needs 10 rolls where wall area divided by roll area says 7. Half drops add half a repeat to every drop after the first. Rolls keep the units on their label, 53 cm × 10 m or 20½ in × 33 ft, and each room’s walls can be picked one by one for a feature wall.
The drywall calculator. Sheets for walls and ceilings with doors and windows figured solid, the way the CGC handbook says estimators count — or taken off, for big openings — plus the joint tape, compound and screws from USG’s published rates.
The paint, wallpaper and drywall pages now share one ceiling height.
Every calculator page loads less code, compressed: 7 KB less on the main calculator (a sixth), 9 KB less on the converters (two fifths) and 12 to 16 KB less on each estimator (about a quarter).

18 September 2026

Corrections

Unit conversion. Twelve inches came to 0.9999999999999998 feet, because two decimal factors were multiplied together. Conversions now go through exact integer ratios, so twelve inches is one foot and an acre is exactly 43,560 square feet.
L-shaped rooms. The drawing cut the notch from the wrong corner, so the picture disagreed with the area. A property test now checks that every drawing encloses exactly the area the calculator reports.
Triangle labels. Sides were drawn sorted by length but labelled in the order they were typed, so “Side A” on the drawing could be a different number from Side A in the form.
Comparison drawings. A comparison larger than the area was drawn as an empty frame. Those drawings now reshape the area to fit, and each comparison says how many objects fit laid flat — which is not the same as how many fit by area.
Empty cutout rows. Adding a cutout and not filling it in broke the running total. An empty row now counts as nothing.

New

The carpet calculator. Carpet is cut off a fixed-width roll, so it lays every room both ways in drops and keeps the way round that buys less carpet, counting the seams and the real offcut — and shows what the “area plus a percentage” shortcut would have said beside it. It allows the 3 inches at every wall the installation standard asks for, which is why a room exactly a roll wide takes a second drop. It also tries every roll width a shop stocks against your rooms and says when another one buys less carpet — a 14 × 10 room takes a tenth less off a 15 ft roll laid across. The price keeps the unit it was quoted in, per square foot, yard or metre.
The tile calculator. It works out the minimum grout joint the tile standards set for the tile you are laying — 1/16 in, or 1/8 and 3/16 in for rectified and calibrated tiles over 15 inches — and says when yours is under it. Tiles are counted in the cells they really occupy, joint included, and grout is worked out as a volume from geometry. That geometry reproduces Custom Building Products’ and Laticrete’s published coverage charts to within half a per cent.
The flooring calculator. Floor area plus the waste your laying pattern really costs, into whole boxes. The waste figures are the published ones, and where the manufacturers disagree — they do, about diagonals — the page says so instead of picking one.
The baseboard calculator. It plans the cuts wall by wall rather than dividing, because a room with four 3 m walls needs four 4.2 m lengths and not the three that 12 ÷ 4.2 suggests. The cut plan is printed so you can check it against the room.
An estimators page collecting them, and buttons on the calculator that open any of them with your rooms already in place.
The paint calculator. It takes each room’s wall run and ceiling height, subtracts the doors and windows, adds the ceiling if you are painting it, multiplies by the coats and turns the result into containers you can actually buy — gallons and quarts in the US, tins in metric. A button on the square footage calculator opens it with your rooms already in it.
Trust pages: about, contact, privacy, terms, accessibility and this changelog. Breadcrumbs on every page, with matching structured data, and a share image generated for each page from the site’s own SVG.
Converters for square feet to square metres, acres to square feet and square feet to square yards, each working in both directions, plus five “how big is N square feet” pages with scale drawings and sourced real-world comparisons.
The measuring guide and the methodology page, which publishes every formula and conversion constant with its source.
Waste, cost and printing: waste percentages, price per square foot or metre, tax, and a printable one-page summary with the room table and the drawings.
The calculator itself: seven shapes, smart input (12'6", 12 ft 6 in, 3,5 m), several rooms, cutouts and extra areas, share links that carry the whole calculation, and a recent list stored in the browser.