Square feet calculator
Work out the square footage of a room, or several rooms added together, and the same area in square metres.
Square metres from the legal definition of a foot.
Result
The area is 120 square feet, or 11.148 square metres.
square feet
| In square feet | 120 sq ft |
|---|---|
| In square yards | 13.333 sq yd |
Show the workings
| Step | Sum | Answer |
|---|---|---|
| Area | 12 ft × 10 ft, in metres: 3.658 m × 3.048 m | 11.148 m² |
| One square foot in square metres | (0.9144 ÷ 3 m)² | 0.093 m² |
| Total in square feet | 11.148 ÷ 0.0929 | 120 sq ft |
Where the figures come from
- A yard in metres: 0.914 m per yard. Source: Weights and Measures Act 1985, Schedule 1. Checked 13 November 2026.
- Feet in a yard: 3 feet per yard. Source: Weights and Measures Act 1985, Schedule 1. Checked 13 November 2026.
How to work out square feet
Multiply the length by the width, both in feet. A room 12 ft by 10 ft is 12 × 10 = 120 square feet.
If a size has inches, turn them into part of a foot first by dividing by 12: 10 ft 6 in is 10.5 ft. For an L-shaped room, split it into two rectangles and add them with "Add another area".
Square feet to square metres
A square foot is 0.0929 square metres, because a foot is defined in law as a third of 0.9144 metres. So 120 square feet is 11.148 square metres.