HOW IT WORKS
The calculation
For each rectangle, multiply length by width. Convert inch measurements to feet first, then add each area.
General Construction
Square Footage Calculator
Add rectangular areas one at a time to total a home, room, or project footprint. Choose feet or inches for each measurement.
Keep in mind
This totals rectangular measurements. Break irregular shapes into separate rectangles without overlap.
COMMON QUESTIONS
About square footage estimates
Can I combine several rooms?
Yes. Add a separate row for each rectangular space; the total is the sum of all room areas.
Does this handle L-shaped rooms?
Not directly. Divide an irregular room into non-overlapping rectangles and add each section as a separate area.
Want to understand the assumptions? Read the square footage estimating guide →