Square Footage Calculator (Rectangular)
Length × width = ft². The simplest area calc.
Result
Loading calculator…
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How to use this calculator
- Enter length and width.
- Read area in ft², m², and acres.
About this calculator
The most basic area formula. Use for any rectangular space. Conversions: 1 yd² = 9 ft²; 1 m² ≈ 10.76 ft²; 1 acre = 43,560 ft².
Frequently asked
How many ft² in an acre?+
43,560 ft². A football field (excluding end zones) is ~1 acre.
ft² to m²?+
Multiply by 0.092903 (or divide by 10.764).
Yards to feet?+
1 yard = 3 feet. 1 yd² = 9 ft².
For irregular rooms?+
Break into rectangles and sum, or use square-footage-irregular.
Including walls?+
No — this is interior floor area. Outside-wall measurement adds 4-8 inches per side.
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