Free tool
Spring rate calculator
Use your bike geometry, rider weight, and target sag to get a practical rear spring-rate starting point.
Free toolNo login requiredGreat first estimate
Next reads
Use the result, then refine the setup
Spring rate is the starting point. These guides help you decide what to change next once the baseline is close.
Guide
MTB Spring Rate Calculator
Learn how to read the output and when the number still needs on-trail validation.
Guide
How To Tune MTB Suspension
Move from spring rate into rebound, compression, and symptom-based testing.
Paid access
AI MTB Suspension Tuning
See when a bike-specific paid workflow is worth using after the baseline is set.