Square Footage Calculator

Square footage measures the flat area of a floor, wall, or surface. For a rectangle, multiply length by width. Switch to metric for the same math in meters → square meters.

Irregular rooms can be split into smaller rectangles — calculate each area and add them. Subtract alcoves or closets only if you are excluding them from the job. For sloped ceilings or angled walls, use the average height or break the wall into sections.

Example: a 14 ft × 12 ft bedroom has 168 sq ft of floor area (14 × 12). That equals about 15.6 m² — useful when comparing tile or flooring sold in metric units.

Flooring and carpet are sold by the square foot or square metre, but installers often quote by the room rather than by the raw area. Add 5–10% for cuts and pattern matching on plank flooring, and more for diagonal layouts — the area figure alone understates what you will actually buy.

One square metre equals about 10.76 square feet, so a 15.6 m² room is 168 sq ft. Mistaking the two units by a factor of ten is a common ordering error when comparing metric tile packs with US room measurements — convert once here before shopping.

Wall area for paint or wallpaper is length of each wall times height, not floor square footage. A 14 × 12 ft room with 8 ft ceilings has 416 sq ft of wall before openings (two 14-ft walls and two 12-ft walls × 8), which is why paint calculators ask for perimeter and height separately.

L-shaped and open-plan spaces overcount if you multiply the longest overall length by the longest overall width. Split into rectangles that do not overlap, sum those areas, then subtract closets or stairwells you will not finish.

Sloped ceilings and attic rooms need average height or segmented wall strips for paint volume; this tool reports flat floor or wall rectangle area only.

For irregular rooms, break the space into rectangles, sum each area, then subtract closets or stairwells you will not floor. Odd-shaped nooks add up quickly when measured separately instead of guessing one overall length and width.

Open floor plans with half-walls still count enclosed area — measure to the wall centerline your flooring installer will actually cover.

Bay windows and alcoves add area when you measure each recess separately instead of rounding the room to a simple rectangle.