Chain Length Calculator

Summary

Enter sprocket teeth counts, chain pitch, and center distance to instantly find the required chain length and number of links.

How it works

1. Enter the number of teeth on the small (driver) sprocket.
2. Enter the number of teeth on the large (driven) sprocket.
3. Enter the chain pitch — the distance between link pins (e.g. 0.5 in for #40 chain).
4. Enter the center distance between the two sprocket shafts.
5. The calculator applies the standard ANSI chain length formula and rounds links up to the nearest even number.
6. The corrected center distance for the rounded link count is shown so you can set your tensioner accurately.

Use cases

• Sizing roller chain for a bicycle, go-kart, or mini-bike drivetrain.
• Designing conveyor or power-transmission chain drives in machinery.
• Replacing a worn chain — find the exact link count before ordering.
• Checking whether an existing chain is long enough after repositioning sprockets.
• Verifying center-distance adjustments when swapping to a different sprocket ratio.
• Teaching mechanical engineering students the chain drive design process.

Frequently Asked Questions