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Square Feet Calculator

Add labeled sections with independent shapes and measurement units, then total their areas.

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Square Feet Calculator formula

Rectangle = length × width. Triangle = base × height ÷ 2. Circle = π × radius².

Worked example

A 12 ft by 10 ft room has an area of 120 square feet.

How to use this calculator

  1. Add or label an area.
  2. Choose its shape, unit and dimensions.
  3. Review each area and the combined total.

Important assumptions and limitations

This calculates area, not perimeter. Measure consistently and allow separately for waste when buying materials.

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Frequently asked questions

Can rooms use different units?

Yes. Each section converts independently to square feet.

Does this include material waste?

No. Add your own waste allowance after calculating the measured area.