Square Footage Calculator

Find area for common shapes and combine multiple sections for a total square footage estimate.

Rectangle area

Rectangle area: 0 sq ft

Circle area

Circle area: 0 sq ft

Triangle area

Triangle area: 0 sq ft

Total area

Total square footage: 0 sq ft

Tip: set any unused shape values to 0.

Combining shapes for an irregular room

Many real rooms aren't a single simple shape — an L-shaped room, a room with a bay window, or a space with a rounded reading nook can often be broken down into a rectangle, a circle (or partial circle), and a triangle, calculated separately and added together. Setting any shape's dimensions to 0 removes it from the total, letting you use just the sections that apply to your space.

Frequently asked questions

How do I measure an L-shaped room? Split it into two rectangles (treat one as the "rectangle" section and calculate the other separately, then add the two totals together), or extend this approach across multiple visits to the calculator for more complex shapes.

Why use diameter instead of radius for the circle? Diameter is easier to measure directly with a tape measure across a round area (like a circular rug or fountain) — the calculator halves it internally to get the radius needed for the area formula.

What is this square footage typically used for? Common uses include estimating flooring, paint, or carpet needed for a room, or ballpark real estate size comparisons — for material purchases, also check the material-specific calculators (flooring, paint, tile) for waste-factor-adjusted quantities.