Length times width, in metres
A square metre is the area of a square one metre on each side. For any rectangle, multiply the two sides measured in metres. Measure wall to wall on the inside and take each dimension twice. For an L-shaped or T-shaped room, cut it into rectangles, work out each area and add them.
Other shapes
- Circle. area = π × radius². A round patio 3 m across has a 1.5 m radius, so about 7.07 m².
- Triangle. area = ½ × base × height, using the perpendicular height, not the sloped side.
- Trapezoid. area = ½ × (base + top) × height — useful for a sloped or tapering lot.
Square metres to square feet
Multiply m² by 10.764 for square feet; multiply square feet by 0.0929 to go back.
| Square metres | Square feet | Rough sense of size |
|---|---|---|
| 5 m² | 53.8 sq ft | small bathroom |
| 12.5 m² | 134.6 sq ft | one parking space |
| 20 m² | 215.3 sq ft | a living room |
| 50 m² | 538.2 sq ft | a studio flat |
| 100 m² | 1,076.4 sq ft | a two-bed flat |
Larger land units follow on: 100 m² is one are, and 10,000 m² is one hectare.
Common questions
How do I work out the square metres of a room?
Measure the length and width in metres and multiply them. A room 4 m by 5 m is 20 m2. For an L-shape, split it into rectangles, work out each one and add them up.
How many square feet is a square metre?
One square metre is 10.764 square feet. To go the other way, multiply square feet by 0.0929. So 100 sq ft is about 9.3 m2.
How much extra should I buy for tiles or flooring?
Add 10% to 15% on top of the measured area for cutting waste, more for diagonal or patterned layouts. For 50 m2 of tile, order about 55 to 58 m2.
