Circle Calculator
Calculate all circle properties from any known value: radius, diameter, circumference, or area.
Input Value
Enter the radius of the circle
Circle Formulas
Circumference
C = 2πr = πd
Area
A = πr² = π(d/2)²
Relationships
d = 2r
r = C / 2π = √(A / π)
Related Calculators
Circle Properties
Radius5
Diameter10
Circumference31.4159
Area78.5398
Visualization
Ad Space
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