Square Footage Calculator

How to use

1. 1Pick whether you want to enter dimensions in feet and inches or in meters.
2. 2Set the shape for each room: rectangle, triangle, circle, or trapezoid. Enter the lengths.
3. 3Add more rooms with Add room if you are measuring a multi-room project.
4. 4Adjust the waste percentage and optional price-per-unit to get an estimated cost. Copy the summary when you are done.

About this tool

Square Footage Calculator measures the floor area of one or more rooms or surfaces, then sums them into a single project total. Each row supports a different shape: rectangle (length and width), triangle (base and height, or Heron's formula from three sides), circle (diameter to pi r squared), or trapezoid (two parallel sides plus the perpendicular height between them). Inputs accept feet plus inches or meters, and the result can be displayed in square feet, square meters, square yards, square inches, or square centimeters. A waste percentage adds a flooring or tile overage on top of the raw total, and an optional price-per-unit field turns the area into an estimated project cost in your chosen currency. The quantity field lets you multiply a single room layout for repeated bays, identical bedrooms, or other duplicate spaces without re-entering dimensions. Useful for flooring, painting, tile, carpet, sod, decking, real-estate listings, and quick room-size sanity checks. All math runs locally in your browser.

Free to use. Works in your browser. No signup, no login.