circles

Given any dimension of a circle, all the others can be calculated.

drawing of a circle with circumference, radius and diameter labeled

=
=  
=
=

Click anywhere outside the boxes to calculate.

Some equations

circumference = pi × diameter

area = pi × radius2

home| numbers index| your comments drawing of envelope| about| help|

privacy

terms of use

Copyright © 2001 Sizes, Inc.  All rights reserved.
Last revised: 1 April 2003.