Square Footage Calculator
Enter a length and width to get the area in square feet — plus square yards, square meters, and acres. Add multiple rooms or rectangles to total a whole job.
Areas (feet)
×
Tip: for an L-shaped room, split it into rectangles and add each as its own area.
Total area
Square feet
0 sq ft
Square yards0
Square meters0
Acres0
How to calculate square footage
Square footage is simply length × width measured in feet. For rooms that aren't a perfect rectangle, divide the floor into rectangles, find each one's area, and add them up. For circles use π × radius², and for triangles use ½ × base × height.
Measure a whole house in minutes, not hours
ProBuildCalc turns your iPhone's LiDAR scanner into a job-site measuring kit — walk the space and it captures the square footage, material takeoff, and a blueprint automatically. No tape measure, no graph paper.
Square footage FAQ
- How do I calculate square footage?
- Measure the length and width of the area in feet and multiply them: length × width = square feet. A room that's 12 ft by 10 ft is 120 square feet.
- How do I find the square footage of an L-shaped or irregular room?
- Break the space into rectangles, calculate the square footage of each, and add them together. Use the “Add an area” button above to total several rectangles at once.
- How many square feet are in a square yard?
- There are 9 square feet in 1 square yard, so divide your square footage by 9 to get square yards — useful for carpet and some flooring sold by the yard.
- How do I convert square feet to acres?
- One acre is 43,560 square feet, so divide your total square footage by 43,560. The calculator shows acres automatically.