OTHER · SQUARE FOOTAGE
Square Footage Calculator
Calculate the exact square footage (or square metres) of a rectangular room or area by entering length and width. Instant, accurate, and unit-aware.
About This Calculator
Enter the length and width of a room or area to get the exact square footage (or square metres). Works instantly in either unit — just pick ft or m and the calculator shows the result in both systems.
How It Works
Enter the length and width in your chosen unit (feet or metres). The calculator multiplies them to get the exact area — no estimates, no coverage constants. The result is shown in the selected unit and automatically converted to the other unit for reference.
The Formula
Area = Length × Width. For a 20 ft × 15 ft room: 20 × 15 = 300 ft². To convert between units: 1 ft² = 0.09290304 m² (exact NIST factor).
Frequently Asked Questions
- Is this calculator exact or an estimate?
- Exact. This calculator multiplies length by width using precise arithmetic. It does not use any rule-of-thumb coverage factors — what you enter is what you get.
- How do I calculate square footage of an L-shaped room?
- Divide the L-shape into two rectangles, calculate each separately, then add the results. For example, an L-shaped room can be split into a 10×12 ft section (120 ft²) and a 6×8 ft section (48 ft²), giving 168 ft² total.
- How many square feet is a 12×12 room?
- 144 square feet (12 × 12 = 144 ft²).
- How do I convert square feet to square metres?
- Multiply by 0.09290304. For example, 300 ft² × 0.09290304 = 27.87 m². The calculator does this conversion automatically.