Calculating a Cake Circumference

To calculate the circumference (the perimeter) of a cake using pi (3.14), multiply the diameter of the cake times pi(or simply multiply by 3 and add a little). You may need to calculate the circumference to cut out strips of paper to line the inside of a cake pan, for example, or if you are making a chocolate band to wrap around a finished cake. The chart below shows the basic math using pi.