Square Footage Calculator
Measure length and width in feet to get the area in square feet. Add a price per square foot to estimate material cost, or multiple areas for several rooms.
Area = length × width. For materials like flooring or sod, add 5–10% extra for waste and cuts.
How to use this calculator
Enter the length and width of the space in feet. The calculator shows the total square footage right away. If you're measuring several identical spaces, set the number of areas. Add an optional price per square foot to estimate the cost of flooring, tile, paint, or sod.
How square footage works
Square footage is simply area: length × width. As long as both measurements are in feet, the result is in square feet (ft²). For rooms that aren't a simple rectangle, break them into rectangles, find each area, and add them up.
Worked example
A living room measures 12 ft × 10 ft = 120 ft². If new flooring costs $3.50 per square foot, the material runs about $420 — and you'd buy roughly 10% extra (≈132 ft²) to allow for cuts and waste.
The formula
Area (ft²) = Length (ft) × Width (ft) × Number of areas
To convert to square yards, divide square feet by 9. To estimate cost, multiply area by price per square foot.
Frequently asked questions
How do you calculate square footage?
Multiply length by width, both measured in feet. A room that is 12 ft by 10 ft is 120 square feet. For several identical areas, multiply by the number of areas.
How do I find square footage of an L‑shaped or irregular room?
Split the space into rectangles, calculate each one's area with this tool, and add them together. For triangles, use ½ × base × height.
How many square feet are in a square yard?
One square yard equals 9 square feet. To convert square feet to square yards, divide by 9 — the calculator shows this automatically when you don't enter a price.
How much extra material should I buy?
For flooring, tile, sod, or carpet, add about 5–10% to your total square footage to cover cuts, waste, and mistakes. Buy a little more than the exact area.