Enter the number of spiral rings, the outside spiral diameter, and the inside spiral diameter into the calculator to determine the spiral length.

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## Spiral Length Formula

The following equation is used to calculate the Spiral Length.

SL = 3.14159*N*(OD+ID)/2

- Where SL is the spiral length
- N is the number of rings
- OD is the outside diameter
- ID is the inside diameter

The units for the OD and ID should remain the same. The result will be the spiral length in the same units.