Formula
Rectangle: A = L × WCircle: A = π × (d ÷ 2)²Triangle: A = ½ × b × hTrapezoid: A = (b₁ + b₂) ÷ 2 × h1 m² = 10.7639 ft² How it works
Square footage is the floor area of a space measured in square feet. For a rectangular room, multiply the length by the width; a 12 ft by 10 ft bedroom is 120 sq ft. Measure wall to wall at floor level and round up to the nearest inch.
Irregular rooms are easiest to handle by splitting them into simple shapes — an L-shaped room is two rectangles, a bay window is a trapezoid — and adding the pieces. Run the calculator once per piece, or use the quantity box for identical areas such as several same-size bedrooms.
You can mix units: enter dimensions in feet, inches, yards or metres and switch the result between square feet, square metres, square yards and acres. Add a price per square foot to estimate flooring, carpet, sod or cleaning costs.
Frequently asked questions
How do I convert square feet to square meters?
Multiply by 0.0929 (or divide by 10.764). 120 ft² is about 11.15 m².
How do I measure a room with inches?
Enter feet and inches as decimal feet (10 ft 6 in = 10.5 ft) or switch the unit to inches; 126 in × 120 in works just as well.
Does square footage include walls and closets?
For flooring, measure each area you will cover, including closets. Real-estate listings follow separate rules (such as ANSI Z765 in the US) that measure finished living area from exterior walls.