Square Footage Calculator

Square feet of a room, house or yard: rectangles, circles and triangles added together, feet and inches accepted, with m², square yards, acres and cost.

Square footage is length × width in feet. A 12 × 10 ft room is 120 ft². Measurements in feet and inches convert by dividing the inches by 12, so 12 ft 6 in is 12.5 ft, and a 12 ft 6 in × 10 ft 3 in room is 12.5 × 10.25 = 128.1 ft². You can type 12'6 straight into this calculator. Rooms and plots that aren't rectangles can be split into rectangles, circles and triangles and added together, and the total is shown in square feet, square metres, square yards and acres, with an optional cost per square foot.

Units
Area
ft
ft
Feet and inches work too: type 12'6 or 12.5.
Square feet
120

ft²

Square metres
11.15

m²

Square yards
13.33

yd²

Acres
0.0028

43,560 ft² each

How it was worked out
  1. Area: 12 ft × 10 ft = 120 ft²

Common use cases

  • Square footage of a room for flooring, carpet or paint
  • The area of a house, apartment or extension
  • Yard, lawn and garden areas for sod, mulch or fertilizer
  • Price a job quoted per square foot

How to use

  1. Enter the length and width of each area in feet, or feet and inches such as 12'6.
  2. Change a row to a circle or triangle for round and angled spaces, and add as many areas as you need.
  3. Read the square feet, square metres, square yards and acres.
  4. Enter a price per ft² for a cost estimate.

FAQ

How do I calculate square footage?

Multiply length by width, both in feet. For an L-shaped room, split it into two rectangles, work out each and add them. For a circle, π × radius²; for a triangle, half the base times the height.

How do I convert feet and inches?

Divide the inches by 12 and add them to the feet: 10 ft 3 in is 10.25 ft, 6 ft 9 in is 6.75 ft. This calculator also accepts 10'3 directly.

How many square feet are in a square metre, a square yard and an acre?

1 m² is 10.764 ft², a square yard is 9 ft², and an acre is 43,560 ft².

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