About the Floor Area Calculator

Rectangular floor area is the product of length and width. The same 20 × 20 ft room measures 400 sq ft, 37.2 sq m, and 44.4 sq yd — the three units most commonly quoted in real-estate listings worldwide, which is why comparing international properties requires conversion.

Beyond the Rectangle

Real floors aren't always rectangular: split L-shaped rooms into rectangles, subtract closets and stairwells, and measure to the interior walls (excluding trim). For material purchasing, add 5–10% for waste — the perimeter figure helps budget baseboards and moldings.