What is the Circumference?

The circumference is the distance around the edge of a circle. It is essentially the perimeter of a circle.

Formula for Circumference

The circumference CCC of a circle can be calculated using either of these formulas:

C=2πrC=2\pi rC=2πr

or

C=πdC=\pi dC=πd

where:

• rrr = radius of the circle (distance from the center to the edge)
• ddd = diameter of the circle (distance across the circle, passing through the center)
• π\pi π (pi) ≈ 3.14159

Example

If a circle has a radius of 5 units, its circumference is:

C=2π×5=10π≈31.42 unitsC=2\pi \times 5=10\pi \approx 31.42\text{ units}C=2π×5=10π≈31.42 units

If you'd like, I can help you calculate the circumference for a specific circle—just provide the radius or diameter!