# How do you find the radius of a circle?

If you have the circumference- You have to divide the circumference by 2*Pi

If you know the diameter the radius is simply half the diameter.

If you know the area of a circle, the radius can be found using the formula : R = √A/π

where: A is the area of the circle and π is Pi, approximately 3.142.

### What is the radius and the area of a circle?

The radius of a circle is the distance from the center to any point on the circle. The area is the space within the circle. The formula to find the area is πr2. r stands for the radius of the circle. If you want to find the radius, you can work backwards from the area or the circumference, which is the perimeter of the circle. The formula for circumference is 2πr.