Enter the mean diameter and the total number of coils into the calculator to determine the spring wire length.

Spring Wire Length Formula

The following equation is used to calculate the Spring Wire Length.

SWL = PI* D * N 
  • Where SWL is the spring wire length
  • D is the mean diameter of each coil
  • N is the total number of coils

To calculate the spring wire length, multiply the diameter of the coil by pi, then multiply the result by the number of coils.

What is a Spring Wire Length?


A spring wire length is the total length of a spring if it were stretch linearly. The length depends on the diameter of the coils and the total number of coils.

How to Calculate Spring Wire Length?

Example Problem:

The following example outlines the steps and information needed to calculate the length of a spring wire.

First, determine the diameter of the coils. The mean diameter for this example is found to be 3 inches.

Next, determine the total number of coils. This spring is found to be 20 coils.

Finally, calculate the spring wire length using the formula above:

SWL = PI* D * N

SWL = 3.14159* 3 * 20

SWL = 188.4954 inches