Circle Area & Circumference Calculator from Radius

Would you like to know the area or the circumference of a circle and the only piece of information you have is the radius of the circle? Use our Circle Area & Circumference Calculator from Radius calculator that gives you the circumference and the area of a circle – the only thing you have to enter is the radius of the circle.

The formula used for the calculation of a circle’s circumference and area from radius:

• The formula used for the calculation of circumference: C = 2 ∙ r ∙ π
• The formula used for the calculation of area: A = r2 ∙ π