Circumference Calculator

Definition of circumference

Parts of a Circle

• r – Radius
• D – diameter
• C – Circumference
• A – Area

Formula for circumference

• If given Radius of a circle (r):

  ${C = 2\pi r}$

• If given Diameter of a circle (D):

  ${C = \pi D}$

• If given Area of a circle (A):

  ${C = 2\pi \sqrt{\dfrac{A}{\pi}}}$

Where π is a constant approximately equal to 3.14159.