Square Footage Calculator
Enter a length and width to get the area in square feet, square yards, square meters and acres. Add more areas to total several rooms.
Enter a length and width to see the area.
How to Calculate Square Footage
For a rectangular area:
Square feet = Length × Width
Example: 20 ft × 30 ft = 600 sq. ft.
If a measurement is in inches, convert it to feet first by dividing by 12, then multiply as usual.
Example: 150 in ÷ 12 = 12.5 ft, so a space that is 150 in × 20 ft is 12.5 ft × 20 ft = 250 sq. ft.
Common Square Footage Conversions
| Unit | In square feet |
|---|---|
| 1 square yard | 9 sq. ft. |
| 1 square meter | ≈ 10.764 sq. ft. |
| 1 acre | 43,560 sq. ft. |
| 1 square inch | 1/144 sq. ft. (≈ 0.00694) |
Calculating Multiple Rooms
Break an L-shaped or multi-room space into rectangles, find the area of each, then add them together.
Example: 20 ft × 30 ft (600 sq. ft.) + 12 ft × 15 ft (180 sq. ft.) + 10 ft × 8 ft (80 sq. ft.) = 860 sq. ft.
In the calculator above, use Add Another Area for each rectangle. You can name each one (Office, Lobby, Warehouse) and remove any you do not need.
Frequently Asked Questions
How do I calculate square footage?
Multiply the length of an area by its width when both measurements are in feet. For example, 20 ft × 30 ft = 600 sq. ft.
How many square feet are in an acre?
43,560 square feet.
How many square feet are in a square yard?
9 square feet. To convert square feet to square yards, divide by 9.
How many square feet are in a square meter?
About 10.764 square feet. To convert square feet to square meters, multiply by 0.0929.
Can I calculate multiple rooms?
Yes. Calculate each room separately and add the areas together. This calculator does it for you: use Add Another Area for each room, and the total updates as you type.
What if my measurements are in inches or meters?
Pick the unit next to each measurement. The calculator converts to feet before multiplying, so you can mix units, such as a length in feet and a width in inches.
Does square footage include walls?
This calculator only works out the mathematical area of the dimensions you enter. Whether walls, columns or shared spaces are included depends on the purpose. Leases, appraisals, listings, building codes and construction documents can each follow a different measurement standard, so the calculated area here is not a substitute for any of them.
Calculator Disclaimer
This calculator is provided for general informational purposes and performs mathematical calculations based solely on the information entered by the user. Results are estimates and may not reflect measurement standards used for architectural, engineering, construction, appraisal, leasing, legal, insurance, or other professional purposes. Verify measurements and consult the appropriate professional when accuracy or a particular measurement standard is required.