Square Footage Calculator
Calculate area for any room shape, in square feet, square meters, or square yards.
Pick a shape, enter the dimensions, get the area. Useful for flooring estimates, paint coverage, rental listings, and renovation planning.
Room shape
How square footage is calculated
Square footage is the area of a flat surface, measured in square feet. The formula depends on the shape:
- Rectangle: length × width
- Square: side × side (or side squared)
- Triangle: 0.5 × base × height
- Circle: pi × radius squared
For irregular rooms, split the room into simple shapes (rectangles and triangles), calculate each one, and add them together.
When you would use this
Estimating flooring needs, calculating paint coverage, sizing rugs or area carpets, determining property tax based on square footage, comparing rental listings, calculating HVAC capacity, or planning a renovation. For paint specifically, also check our Paint Coverage Calculator which uses square footage as one input.
A reminder about wall area
This calculator returns floor or surface area. For wall area (such as for paint or wallpaper), measure room perimeter, multiply by ceiling height, and subtract windows and doors. A 12 by 14 foot room with 9 foot ceilings has roughly 468 square feet of wall area, not 168.