Circle Calculator
Calculate all properties of a circle by entering any known value.
Results
Radius
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Diameter
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Circumference
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Area
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Circle Formulas
A circle is a perfectly round shape where all points on the edge are equidistant from the center. The distance from the center to the edge is called the radius.
Key Formulas
- From radius (r): Diameter = 2r, Circumference = 2πr, Area = πr²
- From diameter (d): Radius = d/2, Circumference = πd, Area = π(d/2)²
- From circumference (C): Radius = C/(2π), Diameter = C/π, Area = C²/(4π)
- From area (A): Radius = √(A/π), Diameter = 2√(A/π), Circumference = 2π√(A/π)
Note: This calculator uses the mathematical constant π (pi ≈ 3.14159) for precise calculations. All results are displayed with 4 decimal places for accuracy.
This calculator provides mathematical calculations for circles based on standard geometric formulas. Results are accurate to four decimal places. While we strive for accuracy, please verify important calculations independently. This tool is for educational and informational purposes.
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