Square Footage Calculator
Calculate area in square feet for rooms and projects, plus total material cost.
Updated September 2026
This square footage calculator measures the area of a space and helps you price materials for it. Choose a shape — rectangle, circle or triangle — enter its dimensions, and it returns the total area in square feet along with square yards and square metres for easy comparison.
Set a quantity to add up several identical areas at once, such as multiple rooms or panels, and add a price per square foot to estimate the material cost. It is handy for flooring, tiling, turf, carpet and any project quoted by the square foot.
How to use it
- 1Pick the shape that matches the area you are measuring.
- 2Enter the required dimensions in feet.
- 3Set a quantity if you are covering several identical areas.
- 4Optionally add a price per square foot to estimate the total cost.
Frequently asked questions
How do I calculate square footage?+
For a rectangle, multiply length by width. For a circle, multiply pi by the radius squared. For a triangle, take half of the base times the height. This calculator applies the right formula automatically for the shape you select.
How many square feet are in a square yard?+
One square yard equals nine square feet, because a yard is three feet on each side and three times three is nine. To convert square feet to square yards, divide the area by nine.
How do I add extra for waste and cuts?+
Flooring and tiling projects usually need extra material for cuts and mistakes. A common approach is to add 5 to 10 percent to the measured area, which you can do here by increasing the quantity or the dimensions slightly.
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