Square Meter Calculator
Your estimate
- Acres
- 0.003 acres0.001 ha · 120 ft²
- Cost
- $360
Area in square metres (m²) for rooms, floors, walls and gardens — also converts square feet to square metres.
Updated 2026-10-20 · Based on: exact NIST unit definitions.
How to use the Square Meter Calculator
- Pick the shape.
- Enter the sizes in m or cm (each box has its own unit).
- Add a price per m² to estimate tiles, flooring or paint.
- Read m², ft² and the cost.
Formula
Rectangle: length × width (4 m × 3 m = 12 m²). Circle: π × r². Triangle: base × height ÷ 2.
Square feet to square metres: ft² × 0.092903. Square metres to square feet: m² × 10.7639.
Worked example
With the values preset in the calculator above: (Rectangle)
- Length
- 12 ft
- Width
- 10 ft
- Quantity
- 1
- Area
- 120 ft² (13.33 yd²)
- Acres
- 0.003 acres (0.001 ha)
- Cost
- $360
Square feet to square meters (sq ft to sq m)
Switch the calculator to feet, enter the room in feet and read the m² line, or use 1 ft² = 0.092903 m². 100 ft² is 9.29 m², 500 ft² is 46.45 m² and 1,000 ft² is 92.90 m².
Square metres of common sizes
| Length (ft) | Width (ft) | Area |
|---|---|---|
| 10 | 10 | 100 ft² |
| 12 | 12 | 144 ft² |
| 20 | 20 | 400 ft² |
Related guides
Frequently asked questions
How do I calculate square metres?
Multiply the length by the width, both in metres. A room 4 m × 3 m is 12 m². Convert centimetres to metres first (350 cm = 3.5 m).
How many square feet is 1 square metre?
10.764 ft². One square foot is 0.0929 m².
How do I measure an L-shaped room?
Divide it into two rectangles, calculate each and add them — choose L-shape in the calculator.
More calculators
Estimates only — check quantities with your supplier and local building code before you order.