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Square Footage Calculator

Area for rooms, floors and walls — rectangle, triangle or circle, in feet and meters.

Measurements

Total area

Square feet0
Square meters0
Square yards0

Add 5–10% for cuts and waste when ordering flooring or paint.

How it works

Rectangle = length × width. Triangle = ½ × base × height. Circle = π × radius². Results convert automatically to square meters (× 0.0929) and square yards (÷ 9).

Irregular room? Break it into simple shapes, calculate each, then add the areas together.

Shop flooring & materials

Tile, carpet, hardwood and paint from trusted retailers.

Good to know

Square Footage FAQs

How do you calculate square footage?

Rectangle: length × width. Triangle: 0.5 × base × height. Circle: π × radius². Use the same unit throughout.

How many square feet in a 12x12 room?

144 ft² (12 × 12), about 13.38 m².

Square feet vs. square yards?

9 ft² = 1 yd². Divide square feet by 9 for square yards (carpet is often sold this way).

How much extra flooring should I order?

5–10% for normal layouts, up to 15% for lots of cuts and angles.

How do I measure an irregular room?

Split it into rectangles, triangles and circles, add each area together.