Area Calculator Online — Circle, Rectangle, Triangle
Runs 100% in your browser — your files never leave your device.
Square footage for flooring, fabric for a banner, paint coverage for a wall — area questions are constant and the formulas are easy to mix up. Pick a shape, type its dimensions, and read the area instantly. Only the fields the chosen shape needs appear, so there is nothing to configure.
How it works
- 1
Pick the shape
Rectangle, square, circle, triangle, or trapezoid.
- 2
Type the dimensions
Only the measurements the shape needs appear — radius for a circle, base and height for a triangle.
- 3
Read the area
The result updates live as you type, in square units.
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