How this instrument works
A square metre is simply a square one metre on a side, needing no separate definition beyond the metre itself. A square foot inherits from the foot, fixed at exactly 0.3048 m by the 1959 international yard and pound agreement — square that figure and one square foot becomes 0.09290304 m² precisely. Invert it and 10.7639104167 falls out, a decimal that runs on forever (10.76391041670972…) because it reduces to the fraction 1,562,500⁄145,161.
Trades that sell material by area live on both sides of that number. American flooring, tile, turf and epoxy-coating suppliers quote coverage in square feet — a gallon of two-part epoxy might claim 200 ft² per coat — while architectural drawings from Europe, Australia, Japan and most of the rest of the world are dimensioned in square metres. A contractor bidding on a metric floor plan needs this factor before a single material order can be placed.
The same conversion turns up outside flooring, too. Solar installers sizing a rooftop or ground-mount array against a metric site survey, greenhouse growers converting a European glazing spec into US-sourced panel sizes, and HVAC contractors applying rules of thumb like one ton of cooling per 500 ft² of conditioned space all end up multiplying or dividing by 10.7639104167 at some point in the estimate.
- Type your area into Square metres (m2) — it opens at 100, roughly a small warehouse bay or a two-bedroom flat.
- Read Square feet (ft2) directly beneath; it recalculates with every keystroke.
- Coming from room dimensions instead? Multiply length by width in metres first, then enter that product.
- Need to go back to square metres? Multiply your square-foot figure by 0.09290304, an exact reverse factor.
Worked example — coating a 100 m² warehouse floor
A European-designed distribution warehouse specifies a 100 m² loading-bay floor for a two-coat epoxy system, and the US-based applicator's coverage figures are all in square feet. Leave Square metres (m2) at its default of 100 and Square feet (ft2) returns 1076.39104167, call it 1,076 ft².
The chosen coating covers roughly 200 ft² per gallon per coat, so 1,076 ft² divided by 200 ft² per gallon is 5.38 gallons for a single pass. Two coats double that to 10.76 gallons, and the applicator rounds up to twelve 1-gallon pails once a waste allowance for edges, cutting-in and a second-coat overlap is added — a material order that starts from the same 10.7639104167 multiplier every time the site's plans list a room in square metres instead of square feet.
Questions
Is 10.7639104167 an exact conversion, or rounded?
Rounded, at the tenth decimal. Its exact value is the fraction 1,562,500⁄145,161, whose decimal expansion never terminates. The reverse direction is exact, though: 0.09290304 m² per square foot follows directly from squaring 0.3048 m, with nothing approximated. Ten places of the forward factor leaves an error near one part in a hundred billion, far below what any tape measure or laser distance meter can resolve on a job site.
Why can't I just multiply by 3.28 twice, or use the linear factor directly?
Because area scales as length squared, not length. The linear metre-to-foot factor is 3.280839895, and it has to be applied twice for an area — squared, it becomes 10.7639104167 — and three times for a volume. Multiplying a 100 m² floor by 3.280839895 just once gives 328 ft², under a third of the correct 1,076 ft², a mistake that shows up constantly in hastily converted material estimates.
A US paint can says it covers 350 square feet per gallon — how many square metres is that?
Divide by 10.7639104167: 350 ft² divided by that factor is about 32.5 m² per gallon. That is the figure worth writing on a metric site's material schedule, since ordering by the can count alone, without converting the coverage rate, is exactly how a European job runs short of paint partway through the second coat.
How is HVAC sizing affected by working in square metres instead of square feet?
US rules of thumb for residential cooling load, such as one ton of air conditioning per roughly 500 to 600 ft² of conditioned space, are built around square feet. Convert a European floor plan's square-metre area first — 100 m² becomes about 1,076 ft² — before applying that rule, or the resulting tonnage estimate will be badly oversized against the actual floor area.
How many square feet does a roll of artificial turf or synthetic grass cover?
It depends on the roll, but a common landscaping roll 2 m wide by 25 m long covers 50 m², which converts to 538.196 ft² — enough context to check a supplier's stated coverage before ordering enough rolls to cover a converted lawn area quoted from a metric site plan.
Why does my phone's AR measuring app give a slightly different square-metre figure than a laser measure?
LiDAR- and camera-based AR area tools estimate room boundaries from depth data and corner detection, both of which carry a few centimetres of uncertainty per wall — enough to shift a computed floor area by one or two percent next to a dedicated laser distance meter. For a quick estimate that is fine; for a material order worth arguing over, remeasure the critical dimensions by hand.
Does this converter accept negative or zero area values?
No — an area cannot be negative, so the tool asks for zero or more. Enter the magnitude of your measured or drawn area only; if you are working from a signed coordinate calculation in GIS or CAD software, take its absolute value before typing it in here.