Area calculator
Work out the area and perimeter of a square, rectangle, triangle, circle, trapezoid, rhombus or irregular plot, in m², square feet, hectares and acres.
How to useArea calculator
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Area calculator: what it is for
Pick a shape, type the measurements and see the area and perimeter instantly. The result is also converted into square meters, square centimeters, hectares, acres, square feet and square kilometers.
For a four-sided irregular plot, the calculator averages the front with the back and the two sides. A triangle can be worked out from base and height or from its three sides (Heron's formula).
How to use
- Choose the shape and the unit.
- Type the measurements.
- See the area, the perimeter and the conversions.
When to use it
- Find the area of a plot of land or a room.
- Buy flooring, turf or paint.
- Solve geometry homework.
Frequently asked questions
How do I calculate the area of an irregular plot?
Measure all four sides. The calculator averages the opposite sides (front with back and the two sides), which is a good approximation for plots that are nearly rectangular.
How big is a hectare?
10,000 m², or about 2.47 acres. One acre is 4,046.86 m², or 43,560 square feet.
Is it really free?
Yes, 100% free. No sign-up, no subscription and no usage limits. All Tools123 are free.