# Circumference of Cylinder

The circumference of a circle is simply the circumference of the circular base of the cylinder. It is measured in units of length such as m, cm, mm, and ft. Shown below is the circumference (c) of a cylinder with dotted lines.

Let us now learn how to find the circumference of a cylinder with formulas and solved examples.

## Formula

The formula used to calculate the circumference of a cylinder is obtained by multiplying the radius by 2 to obtain the diameter and then multiplying the result with pie (π) = 3.141. Thus, the formula to calculate the circumference of a cylinder is given below:

Circumference (C) = 2πr, here π = 22/7 = 3.141, r = radius

Let us solve some examples to understand the concept better.

## Solved Examples

Find the circumference of a cylinder having radius of 12 inches.

Solution:

As we know,
Circumference (C) = 2πr, here π = 3.141, r = 12 inches
= 2 × 3.141 × 12
= 75.384 inches

A cylinder has a diameter of 18 cm. Calculate the circumference of the cylinder?

Solution:

As we know,
Radius (r) = d/2, here d = diameter = 18 cm
= 18/2 cm
= 9 cm
Now, as we know
Circumference (C) = 2πr, here π = 3.141, r = 9 cm
= 2 × 3.141 × 9
= 56.538 cm