Square Footage Calculator
Calculate square footage for rooms, walls, floors, and other simple shapes, with automatic conversion between square meters and square feet.
- m²
- 20
- ft²
- 215.28
Calculate rooms, walls, and floors
Choose a rectangle, square, triangle, or circle to match the surface. Enter measurements in millimeters, centimeters, meters, inches, or feet and get both m² and ft².
Formulas and example
A rectangle uses length × width, a triangle uses base × height ÷ 2, and a circle uses π × radius². A 5 m by 4 m room is 20 m², approximately 215.28 ft².
Irregular areas and cost
Split an irregular surface into simple shapes, calculate each part, and add the results. The optional price is applied per m²; allow separately for cuts, waste, or installation.
Frequently asked questions
How do I calculate a room or wall area?
For a rectangle, multiply length by width, or wall width by height. Keep both measurements in the same unit.
What is the difference between m² and ft²?
They are different area units. One square meter is approximately 10.764 square feet.
How do I measure an irregular area?
Divide it into simple shapes, calculate each area, and add the results. This tool calculates one shape at a time.
Does the circle use diameter or radius?
The input uses radius; area is calculated as π × radius².
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