Square Footage and Square Metre Calculator

Work out floor area in square metres, square feet and square yards for one room or a whole house, from metric or feet and inches, with a cost estimate.

Reviewed by Dany, RightSums team · Updated

Runs in your browser. Free, no sign-up.

home-energy · Daily life · UK & US

Add each room or shape, pick the units you measured in and the calculator totals the floor area in square metres, square feet and square yards. It handles rectangles, L-shaped rooms split into two rectangles, circles and triangles, and takes metres, centimetres, feet, inches or mixed feet and inches such as 12 ft 6 in. The conversions use the exact legal definitions, so 1 foot is 0.3048 m and 1 square foot is 0.09290304 m². Enter a price per square metre, square foot or square yard to get a cost estimate for flooring, carpet, turf or decorating. It measures flat floor area only, so add an allowance for waste yourself when buying materials.

Accepted inputs

  • Room or shape name
  • Shape: rectangle, L-shape, circle or triangle
  • Measurements in m, cm, ft, in or feet and inches
  • Optional price per m², sq ft or sq yd

Outputs

  • Area of each room
  • Total in square metres
  • Total in square feet
  • Total in square yards
  • Cost estimate

How to use the Square Footage and Square Metre Calculator

  1. Choose the unit you measured in, from metres and centimetres to feet, inches or feet and inches together.
  2. Add each room or area and pick its shape, splitting an L-shaped room into two rectangles that do not overlap.
  3. The calculator converts every measurement to metres using the exact legal definitions, works out each area and adds them up.
  4. It shows the total in square metres, square feet and square yards, and multiplies by your price per unit area if you enter one.

Frequently asked questions

How do I calculate square footage of a room?

Multiply the length by the width in feet. A room 12 ft by 10 ft is 120 sq ft. If you measured in feet and inches, turn the inches into a fraction of a foot first: 12 ft 6 in by 10 ft 3 in is 12.5 × 10.25 = 128.13 sq ft, which is 11.90 m².

How do I work out square metres?

Multiply the length by the width in metres. A room 4 m by 3.5 m is 14 m². If you measured in centimetres, divide each side by 100 first, so 400 cm by 350 cm is also 14 m². The calculator does this for every room and adds them together.

How many square feet are in a square metre?

One square metre is about 10.764 square feet. A foot is exactly 0.3048 m by international definition, so a square foot is exactly 0.09290304 m². That makes a 14 m² room 150.69 sq ft, and a 120 sq ft room 11.15 m².

How do I measure an L-shaped room?

Split it into two rectangles that do not overlap, measure each one and add the areas. A room made of a 5 m by 3 m section and a 2 m by 2 m section is 15 + 4 = 19 m², or 204.51 sq ft. Choose the L-shape option and enter both parts.

How much will flooring cost for my room?

Multiply the floor area by the price per unit area. A 14 m² room at £25 per m² comes to £350. In the US, 120 sq ft at $4 per sq ft is $480. Add around 5 to 10% for cuts and waste, and check fitting costs separately.

Sources

The rates and rules in this tool come from:

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