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Square Footage Calculator

Enter each room's width and length. Get the total square footage.

100% in your browser - no upload, no sign-up.

Quick fill:

How do I measure this?
  1. Run a tape measure along one wall at floor level - that's the length.
  2. Measure the wall at a right angle to it - that's the width. For an L-shaped room, split it into rectangles and add them up.
  3. Write both numbers down before you shop - a phone photo of the tape works great.

Presets are rough starters - measure your real room before ordering.

Total area

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Rooms counted: 1

⚠️ Divide inches by 12 - 10 ft 6 in is 10.5 ft, not 10.6.

Room floor plan with length and width arrows - square footage calculator

How to use this square footage calculator

  1. Choose feet or metres.
  2. Enter each room's width and length; add a row per room.
  3. Read the total in both ft² and m² - it updates live.

How square footage is calculated

Square footage is width multiplied by length for each rectangular area, added together. For rooms that aren't a simple rectangle, split them into rectangles and add each as a separate room. To convert, 1 square metre equals 10.7639 square feet.

Frequently asked questions

How do I calculate the square footage of a room?
Measure the room's width and length in feet and multiply them. A 10 ft by 12 ft room is 120 square feet. For multiple rooms, add each room's area together - this calculator does that for you.
How do I find square footage for an L-shaped room?
Split the L-shape into two rectangles, calculate each one's area, and add them. Add each rectangle as its own room row above.
How many square feet are in a square metre?
One square metre is about 10.76 square feet. This calculator shows both units at once, so you don't have to convert manually.
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