Area of a Circle

Calculate Area of a Circle instantly. Free online calculator with the exact formula, a worked example, and metric units. No signup required.

Area of a Circle

Radiusm
Circle area
78.5398
π·r²Calculate Area of a Circle instantly. Free online calculator with the exact formula, a worked example, and metric units. No signup required.
Radius
5m
Diameter
10m
Circumference
31,42m
Area
78,54

More about: Area of a Circle

What it calculates

The “Area of a Circle” calculator computes Circle area in m² from 1 parameter: radius (m).

A core calculation for studying, engineering tasks, and checking solutions.

Example calculation

With parameters Radius = 5 m the result is 78.54 (π·r²).

How to use

  1. Enter the parameter values — every field above is adjustable with a slider.
  2. The result and related metrics are calculated automatically as you type.
  3. Use the additional metrics shown (if any) where needed.
  4. Copy the result or bookmark the page.

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