Save guides, add subjects and pick up where you left off with your BBC account. The circumference of a circle = \(\pi d\) or \(2\pi r\). Look at the sector of the circle shown below. To calculate ...

It is another name for the perimeter of a circle. The circumference of a circle is calculated using the formula: \(\text{circumference} = \pi \times \text{diameter}\) This number is Pi.