Square Footage Calculator
Add up the square footage of one or more rooms and estimate total project cost.
How do you calculate square footage?
For a rectangular room, square footage is simply length multiplied by width, both measured in feet. For a whole home or multi-room project, measure each room separately and add the totals together. This calculator lets you add as many rooms as you need and instantly sums their combined area.
When is square footage useful to know?
Total square footage is essential for buying the right amount of flooring, paint, carpet, or tile, for estimating renovation costs, and for comparing home listings on a price-per-square-foot basis. Contractors and material suppliers often quote pricing per square foot, so knowing your exact area helps you budget accurately and avoid over- or under-ordering materials.
Tips for measuring accurately
Measure each room at its longest and widest points, and round irregular shapes into rectangular sections you can measure separately and add together. If a project involves waste from cuts or pattern matching, many professionals add 5-10% to the total square footage before ordering materials.
Frequently Asked Questions
How do I measure a room for flooring?
Measure the room at its longest length and widest point using a tape measure, then multiply length by width to get square footage. For closets, alcoves, or bump-outs, measure those sections separately and add them to your total so you don't under-order flooring.
What does price per square foot actually mean?
Price per square foot is the total cost of a material or project divided by the area it covers, letting you compare flooring, paint, or construction quotes on an apples-to-apples basis. Multiply your total square footage by the quoted rate above to estimate overall project cost.
What's the difference between square footage and livable square footage?
Total square footage can include garages, unfinished basements, and porches, while livable (or "heated") square footage only counts finished, climate-controlled space people actually live in. Real estate listings typically advertise livable square footage, which is why a home's total footprint can look larger than its listed size.
How do you calculate square footage of an irregular room?
Break the irregular shape into smaller rectangles or triangles you can measure individually, calculate each section's area, then add them together. This calculator's "Add Another Room" button lets you enter each section as its own row and automatically sums the total.
How do I convert square feet to square meters?
Multiply square feet by 0.0929 to get square meters (or divide by roughly 10.764). For example, a 1,000 square foot apartment is about 92.9 square meters — useful when comparing listings or materials sold in metric units.
How much flooring, paint, or carpet do I need for my square footage?
Start with your total square footage, then add 5-10% extra to cover cuts, waste, and pattern matching for flooring or tile. For paint, one gallon typically covers 350-400 square feet per coat, so divide your wall area (not floor area) by that figure to estimate gallons needed.
What's the average cost per square foot to build or renovate?
New home construction typically runs $150-$300+ per square foot depending on region, materials, and finishes, while renovations vary widely from $20-$60 per square foot for cosmetic updates to $200+ for full gut remodels. Enter your own contractor quote in the cost field above to get a project-specific estimate.
Why do contractors and realtors both quote price per square foot?
Price per square foot gives a quick, standardized way to compare projects or properties of different sizes. It's a useful starting point, but it doesn't account for lot size, ceiling height, finish quality, or location, so it should be used alongside — not instead of — a detailed quote or appraisal.