Square Footage Calculator
ft
ft
Square Feet300.00
Square Meters27.87
Acres0.0069
This square footage calculator multiplies a length by a width to give the area of a rectangular space in square feet, and also reports the same area in square metres and acres. It is the quick tool for sizing a room, a floor, a yard, or a building lot when you just need the rectangular footprint. The conversions make it easy to switch between US and metric units or to express land area in acres.
Formula
sq ft = length × width ; sq m = sq ft ÷ 10.7639 ; acres = sq ft ÷ 43,560
- length
- Length of the space in feet
- width
- Width of the space in feet
- 10.7639
- Square feet per square metre
- 43,560
- Square feet per acre
How it works
- Enter the length of the space in feet.
- Enter the width in feet. Both inputs accept decimals, so 12 ft 6 in becomes 12.5 ft.
- The calculator multiplies length by width for square feet, divides by 10.7639 to get square metres, and divides by 43,560 to get acres.
Worked example
A room that measures 20 ft by 15 ft.
- Square feet: 20 × 15 = 300 sq ft.
- Square metres: 300 ÷ 10.7639 = 27.87 sq m.
- Acres: 300 ÷ 43,560 = 0.0069 acre.
300 sq ft, which is 27.87 sq m or about 0.0069 acre.
Frequently asked questions
- How do I calculate square footage?
- Measure the length and width of a rectangular space in feet and multiply them together. A 20 ft by 15 ft room is 20 × 15 = 300 square feet. Both dimensions must be in the same unit before multiplying.
- How many square feet are in an acre?
- One acre equals 43,560 square feet. This calculator divides your square footage by 43,560 so you can see how much of an acre a given area represents.
- How do I convert square feet to square metres?
- Divide the square footage by 10.7639, since one square metre equals 10.7639 square feet. The calculator does this automatically and shows both values together.
- Can this handle non-rectangular or irregular areas?
- This tool computes the area of a single rectangle from length times width. For L-shaped or irregular spaces, split them into rectangles, calculate each separately, and add the results.