Area Of A Circle Calculator
Calculate the area, circumference, and helpful design insights for any circle.
Distance from the centre of the circle to any point on its edge.
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Circle area
706.86 cm²
A = π × r²
Radius
15.00 cm
Half of the diameter
Diameter
30.00 cm
Distance across the circle
Circumference
94.25 cm
Perimeter of the circle
Area conversions
Radius, diameter & circumference
| Unit | Radius | Diameter | Circumference |
|---|---|---|---|
| Millimeters (mm) | 150.00 | 300.00 | 942.48 |
| Centimeters (cm) | 15.00 | 30.00 | 94.25 |
| Meters (m) | 0.15 | 0.30 | 0.94 |
| Kilometers (km) | 0.00 | 0.00 | 0.00 |
| Inches (in) | 5.91 | 11.81 | 37.11 |
| Feet (ft) | 0.49 | 0.98 | 3.09 |
| Yards (yd) | 0.16 | 0.33 | 1.03 |
Design insights
Quarter circle area
176.71 cm²
Perfect for pizza slices, rounded corners, and quadrant designs.
Half circle area
353.43 cm²
Great for semicircular arches, stages, and window layouts.
Matching square side
26.59 cm
Side length of a square with the very same area.
Sphere surface area
2,827.43 cm²
Surface area if this radius wrapped a full 3D sphere.
Sphere volume
14,137.17 cm³
Volume enclosed by a sphere using the same radius.
How we calculated it
- Given radius = 15.00 cm
- Radius = 15.00 cm
- A = π × r²
- A = π × (15.00 cm)²
- A = 706.86 cm²
