Square Footage Calculator

Add up to three areas in any unit and convert to square yards, metres and acres.

Project Details
Enter your measurements and requirements
Results
Calculated estimates for your project
Square feet120
Square yards13.33
Square metres11.15
Acres0.0028
Roofing squares1.20

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Finished the square footage? Snap a before and after. The photo maker lines them up into one image you can post, and a free Blueprint account keeps the photos with your measurements and materials.

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What are you building?

Pick one for a step-by-step plan with tools, materials and costs, or tell us in your own words.

How to calculate square feet

Split odd shapes into rectangles and add them.

  1. Measure. Measure the length and width of each rectangle.
  2. Multiply. Length x width gives square feet when both are in feet.
  3. Add. Add every rectangle.
  4. Convert. Divide by 9 for square yards, or by 43,560 for acres.

Frequently asked questions

How do I find square feet?

Multiply length by width in feet. A 12 by 10 ft room is 120 sq ft.

What if I measured in inches?

Multiply inches and divide by 144, or switch the unit above.

How many square feet in an acre?

43,560.

How do I measure an L-shaped room?

Split it into two rectangles and add them.