Square Footage Calculator

Enter the length and width of each room or area in feet and inches. Add as many areas as you need, or switch to a circle or triangle, and get square feet, square yards and square metres.

How to calculate square footage

For a square or rectangle, multiply the length by the width:

• Square feet = length (ft) × width (ft)

If your measurements include inches, turn the inches into part of a foot first by dividing by 12. The calculator does this for you, so just type the feet and inches into their own boxes.

Worked examples

• A 12 ft 6 in × 10 ft bedroom: 12.5 × 10 = 125 square feet.
• An L-shaped room: split it into two rectangles, say 12 × 10 ft and 8 × 5 ft. That’s 120 + 40 = 160 square feet. Use “Add another area” for each part.
• A round patio 10 ft across: 3.1416 × 5 × 5 = 78.5 square feet.
• A triangular corner, base 10 ft and height 8 ft: 10 × 8 ÷ 2 = 40 square feet.

Inches to feet

Measuring a room

1. Measure wall to wall at floor level, along the longest straight lines.
2. For odd shapes, sketch the room and split it into rectangles, then measure each one.
3. Include closets if you’re buying flooring for them too.
4. Round each measurement to the nearest inch.

Square feet, square yards and square metres

• 1 square yard = 9 square feet. Carpet is often priced by the square yard.
• 1 square metre = 10.76 square feet.
• 1 acre = 43,560 square feet.

Buying materials by the square foot

For flooring, tile and sod, add extra for cuts and mistakes, usually 5 to 10 percent and more for diagonal layouts. Open “Extra for waste and cost” to add it, along with the price per square foot. For lawns, the sod calculator turns square feet into pieces and pallets.

Frequently asked questions

Results are exact for the measurements you enter. See How We Calculate for the formulas we use.