Circle Circumference Calculator

Compute circumference using formula C = 2πr. Essential for geometry students, engineers, and designers working with circular shapes.

Calculator

Radius (r)

π Value

Result:

Circle Visualization

Circumference: -

About Circle Circumference

The circumference is the perimeter of a circle, calculated using the formula C = 2πr where r is the radius. This measurement is crucial in mathematics, engineering, and daily applications like determining fencing needs or material lengths.

Calculation Example

For a circle with radius 5 units:

C = 2 × π × 5 = 31.4159 units (using π=3.14159)

Common Reference Values

Radius	Circumference (π=3.1416)
1	6.2832
2	12.5664
5	31.416
10	62.832

FAQs

What units should I use?

Use any consistent units (meters, inches, etc.). The result will be in the same units squared.

Why are there different π values?

Different approximations balance precision and simplicity. Math.PI is most accurate for calculations.

Can I calculate with diameter instead?

Yes! Circumference can also be calculated as C = πd where d is diameter (d=2r).

Disclaimer: For informational and educational purposes only. Results may vary based on input values and rounding methods. Always verify critical calculations.

References: Euclidean geometry principles, Circle circumference formula, π approximations historical context

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Circle Circumference Calculator - Compute 2 pi r Fast

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