Area Calculator
Pick a shape and enter its measurements to get the area. Each side has its own unit, so you can enter one in feet and another in inches or meters, then read the answer in square feet, square meters, acres or any other area unit.
- Formula used
- Area = length × width
Saved setups
Save a set of inputs you reuse — your usual rate, your loan, your room sizes — and load it back in one tap.
Your recent calculations
Results you calculate here are kept on this device so you can come back to them.
Formula
How to use it
- Choose the shape.
- Enter each measurement and pick its unit — they do not have to match.
- Choose the unit you want the area in.
- For an L-shaped or irregular space, split it into rectangles and triangles, work out each one, and add them up.
Worked examples
A 12 ft by 10 ft room: 120 ft², which is 11.15 m²
- Area
- 120 ft²
- Formula used
- Area = length × width
A circle with a 2 m radius
- Area
- 12.57 m²
A trapezoid with parallel sides of 8 m and 12 m, 5 m apart
- Area
- 50 m²
Height is not the slanted side
For triangles, parallelograms and trapezoids the height is the perpendicular distance from the base to the opposite side or corner. Using the length of a slanted edge instead is the most common mistake and always overstates the area.
Useful area conversions
1 square foot is 144 square inches. 1 square yard is 9 square feet. 1 acre is 43,560 square feet. 1 square meter is about 10.764 square feet, and 1 hectare is 10,000 square meters, or about 2.471 acres.
Questions people ask
How do I calculate the area of a room in square feet?
Multiply the length by the width, both in feet. A 12 ft by 10 ft room is 120 square feet. If you measured in inches, divide the result by 144.
What is the area of a circle with a 5 ft radius?
π × 5² = 78.54 square feet.
Can I mix feet and inches?
Yes. Set each field to the unit you measured in. A rectangle 10 ft long and 30 in wide comes out as 25 square feet.