Square Footage Calculator

How to calculate square footage

Square footage is simply length × width for a rectangular space. A room that is 12 feet by 10 feet is 120 square feet. The only complication in a real house is that it's rarely one clean rectangle — so this tool lets you add a row for each room or section and adds them into one total, in both square feet and square meters.

Breaking an odd shape into rectangles

Almost any floor plan can be measured by splitting it into rectangles, finding each one's area, and summing them. An L-shaped room is two rectangles; a room with a bump-out is the main rectangle plus the bump. Add a row per piece and the total takes care of itself. For a triangular section, measure it as a rectangle and take half. For a circle, area is π × radius².

Square feet to square meters

One square foot is 0.0929 square meters, and one square meter is about 10.76 square feet. Switch the units selector and the tool reinterprets your measurements and re-prices accordingly, which is handy when a product is sold per square meter but your tape measure is in feet.

Estimating material cost

Enter a price per square foot (or per square meter) and the tool multiplies it by the total area — a quick way to budget flooring, carpet, turf, tile, or paint. For flooring, remember to buy 5–10% extra for cuts, waste, and future repairs; products are sold by the box, so you'll round up to whole boxes regardless.

FAQ

Do I include closets and hallways?

For flooring and paint, include every surface you'll actually cover — closets and hallways included. For a real-estate "living area" figure the rules are stricter (heated, finished space only), so the two numbers can legitimately differ.

What about measuring for an acre or lot size?

An acre is 43,560 square feet. Measure the lot's length and width in feet, total the square footage here, and divide by 43,560 to get acres.

Is the square footage calculator free to use?

Yes, it's completely free with no sign-up, and you can add as many rooms or sections as your floor plan needs.

Can I measure rooms in feet and meters together?

The tool shows your total in both square feet and square meters at once, and you can switch the units selector to enter measurements in whichever system your tape measure uses. That's handy when a product is priced per square meter but you measured in feet.

How do I handle an L-shaped or irregular room?

Split the space into rectangles, add a row for each piece, and the tool sums them into one total. An L-shape is two rectangles; for a triangle measure it as a rectangle and halve it; for a circle use pi times the radius squared.

How much extra material should I buy?

For flooring, carpet, or tile, add about 5–10% over the measured area for cuts, waste, and future repairs, then round up to whole boxes since products are sold by the box. Enter a price per square foot or meter and the tool estimates the material cost for you.