Square Footage Calculator
Find the area of any room, wall, or surface in square feet.
Enter your dimensions to get the area in square feet, square yards, and square meters. For a circle, put the diameter in the Length field; for a triangle, use the base as Length and the height as Width. Use the quantity field to add up several identical areas at once.
How it works
Square footage is just area. For a rectangle it's length × width; for a circle it's π × radius²; for a triangle it's ½ × base × height. To convert, divide square feet by 9 for square yards, or multiply by 0.0929 for square meters.
Frequently asked questions
How do I calculate square footage?
Multiply length by width for a rectangular space. For example, a room that is 12 ft by 10 ft is 120 square feet. For circles use π × radius², and for triangles use ½ × base × height.
How many square feet is a 12×12 room?
A 12 ft by 12 ft room is 144 square feet (12 × 12). A 12×10 room is 120 square feet.
Does this work for circles and triangles?
Yes. Pick the shape, then enter the diameter (for circles) or the base and height (for triangles) in the Length and Width fields.
Can I measure in feet and inches?
Yes — convert the inches to a decimal by dividing by 12. For example, enter 12 ft 6 in as 12.5 ft. The result is the same square footage.
Can I calculate multiple rooms together?
Use the quantity field for several identical areas. For rooms of different sizes, calculate each one and add the results together.
Is this calculator free and private?
Yes. Every CubicCabin calculator runs entirely in your browser, so the numbers you enter are never uploaded or stored. There's no sign-up, no limits, and it keeps working even if you lose connection after the page loads.