Home & Cooking
Square Footage Calculator
Find area in square feet for rectangles, circles, and triangles. Also shows square meters, square yards, and acres.
Shape & dimensions
Area
180 sqft
Square meters
16.72 m²
Square yards
20 sq yd
Acres
0.00413
Frequently Asked Questions about the Square Footage Calculator
How do I calculate square footage?
Enter your measurements in feet, then pick the shape that matches your space. For rectangles, the calculator multiplies length by width. For circles, it uses pi x (diameter / 2)^2, so enter the full diameter, not the radius. For triangles, it computes (base x height) / 2. If your room is L-shaped or irregular, measure it in sections and add the areas together.
How big is 1 acre?
One acre equals 43,560 square feet, which works out to a square roughly 209 ft on each side. For context, a standard American football field including end zones is about 57,600 sq ft, so an acre is around 76% of that.
How do I convert square feet to square meters?
Multiply by 0.09290304. The calculator does this automatically and shows square meters alongside square feet and square yards in the results. For a quick mental estimate, 1,000 sq ft is about 92.9 sq m.
Should I measure irregular rooms in sections?
Yes. Break any L-shaped or non-rectangular room into smaller rectangles, measure each section, calculate the area of each, then add them together. That approach is always more accurate than fitting one large rectangle around an uneven floor plan.
Is square footage measured from inside or outside walls?
It depends on the standard. For a detached single-family home, the ANSI Z765 standard used by US appraisers measures gross living area to the exterior surface of the outside walls, so wall thickness is included. Condos and apartments are often measured by interior space instead. This calculator works with whatever dimensions you enter, so just be consistent about where you measure from.