Circle Area Calculator

Calculate the area of any circle from its radius. Pick any unit for the radius — the result is shown in square meters and re-expressed in the unit you chose, so you always see a number that fits the input. Useful for plates, wheels, plots, pizzas, pipes, lenses, and any round surface.

Your Result

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ResultWhat it means?
—No resultInputs are out of range or the circle could not be computed.
= 0Degenerate circleThe radius is zero — the shape collapses to a point and has no area.
< 1 m²SmallLess than 1 m² — a small plate, a watch face, or a manhole cover.
1 – 10 m²Medium1 to 10 m² — a generous dining table, a small patio, or a backyard trampoline.
10 – 100 m²Large10 to 100 m² — a small apartment floor, a tennis half-court, or a roundabout.
≥ 100 m²Very largeAt least 100 m² — a football field, a stadium pitch, or a small reservoir.

Circle area formula

=

Area equals π times the radius squared — independent of the unit chosen, as long as the radius uses that unit.

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