Measuring a real room
Measure at floor level along the longest run of each wall, and treat an L-shaped room as two rectangles rather than trying to average anything. Alcoves, bay windows and closets are their own small rectangles — add them as extra rows. For flooring you want the floor's own area; built-in cabinets usually stay included, since offcuts rarely match their footprint.
Why you should buy more than the total
Materials are sold in whole boxes and get cut to fit, so the working rule is to order 5–10% over the measured area for straight-lay flooring and 10–15% for tile on the diagonal or patterned layouts. The waste is not optional — it is offcuts at walls, breakage and future repairs. Put the per-unit price in and add your margin on top of the cost shown.
The circle and triangle rows
The circle takes a diameter (measure across the widest point) and uses πd²⁄4; the triangle takes base and height, where the height is the straight-line distance from the base to the opposite corner, not the length of the sloped side. Most odd-shaped rooms break down into rectangles plus one triangle.
Frequently asked questions
How many square feet in a square meter?
One square meter is about 10.76 square feet. The converted total is shown automatically, so you can measure in one system and shop in the other.
Is this the same as the square footage on a property listing?
Not necessarily. Listings often use exterior measurements or include areas by local convention (garages, basements) that a room-by-room total excludes. This calculator gives the sum of what you actually measured.
Is my data stored or sent anywhere?
No. The measurements stay on your machine.
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