Square Footage Calculator

Calculate the area of rooms, walls, floors, circles, and triangles. Add multiple sections together and estimate the total project cost.

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Added Areas

0 areas

Add your first area above.

Optional Cost Estimate

Enter the material or installation price per square foot.

Total Area

Combined Square Footage 0.00 sq ft
Square Yards 0.00 sq yd
Square Meters 0.00 m²
Estimated Cost Enter a price to estimate

Measurements are converted to square feet before being combined. Always confirm product coverage, waste allowance, and project-specific measuring requirements before buying.

How to Calculate Square Footage

For a rectangular room, wall, or floor, multiply the length by the width. A 12-foot by 10-foot room contains 120 square feet.

Rectangle Area = Length × Width

Square, Circle, and Triangle Formulas

A square uses one side measurement. A circle uses its diameter, and a triangle uses its base and perpendicular height.

Square Area = Side × Side
Circle Area = π × Radius²
Triangle Area = Base × Height ÷ 2

Measuring Multiple Rooms or Sections

Divide an irregular space into smaller rectangles, squares, circles, or triangles. Calculate each section separately, then add the areas together. Use the quantity field for repeated rooms, walls, windows, or other identical sections.

Remember Material Waste

This calculator reports measured area without automatically adding waste. Flooring, tile, roofing, wallpaper, and other materials may require extra product for cuts, matching, breakage, or future repairs.