Construction & Home
Square Footage Calculator
Square Footage Calculatorlive
0.0069 acres
300 sq ft
Square footage is the standard measurement for the size of a room, lot, or building, and is calculated by multiplying length by width.
The formula
square footage = length × width
acres = square footage ÷ 43,560
Worked example
A lot measuring 20 ft × 15 ft:
square footage = 20 × 15 = 300 sq ft
acres = 300 ÷ 43,560 = 0.0069 acres
Frequently asked questions
How do I calculate square footage?
Multiply the length of a space by its width, using the same unit of measurement for both, to get the total area in square feet.
How do I convert square feet to acres?
Divide the total square footage by 43,560, since one acre is defined as exactly 43,560 square feet.
What if my space isn't a simple rectangle?
Split the space into rectangular sections, calculate the square footage of each one separately, and add the totals together to get the overall square footage.