Square Footage Calculator
Calculate area in square feet from dimensions. Supports rectangle, triangle, and circle shapes. Convert to square meters and acres.
Area (sq ft)—
Area (sq m)—
Area (acres)—
How to Calculate Square Footage
Rectangle: Area = Length × Width
Triangle: Area = ½ × Base × Height
Circle: Area = π × Radius²
Triangle: Area = ½ × Base × Height
Circle: Area = π × Radius²
Measure dimensions in feet, then multiply according to the shape formula. Convert to square meters by multiplying by 0.0929, or to acres by dividing by 43,560.
Example (Rectangle):
Room: 20 ft × 15 ft
Area = 20 × 15 = 300 sq ft
= 27.87 sq m = 0.0069 acres
Room: 20 ft × 15 ft
Area = 20 × 15 = 300 sq ft
= 27.87 sq m = 0.0069 acres
Common Conversions
1 sq ft = 0.0929 sq m | 1 acre = 43,560 sq ft | 1 sq m = 10.764 sq ft
FAQ
How do I measure an irregular room?
Break the room into rectangles, triangles, or circles. Calculate each section separately and add them together for the total square footage.
Do I include closets in square footage?
For flooring or painting, include all areas you plan to cover. For real estate, follow local standards for livable space measurement.
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Last updated: 2026-08-08