How to use this calculator
- Choose units and the shape that matches the space. Split complex rooms into several shapes and add them up.
- Enter the dimensions.
- Optionally enter a price per square foot or square meter to estimate cost.
Formula
Square footage is an area measurement. Measure in feet; for feet-and-inches measurements, convert inches to decimal feet first (inches ÷ 12).
Rectangle: L × W
L-shape: (L₁ × W₁) + (L₂ × W₂)
Circle: π × (D/2)²
1 m² = 10.7639 ft²; 1 yd² = 9 ft²
Example
- A 12 ft × 10 ft room = 120 ft² = 11.15 m².
- At $4.50/ft² for flooring: 120 × 4.50 = $540 before waste.
Frequently asked questions
How do I convert 10 ft 6 in to decimal feet?
6 in ÷ 12 = 0.5, so 10 ft 6 in = 10.5 ft.
Should I add extra for flooring?
Yes. Add 5–10% for straight layouts and 10–15% for diagonal or patterned layouts to cover cuts and waste. The tile calculator includes a waste setting.
Does home square footage include walls?
Real-estate measurement standards (such as ANSI Z765 in the US) measure finished area to exterior walls. Rules vary by country.