Gear Ratio Calculator
Calculate gear ratio, speed at any cadence, gear inches, and development from chainring, cog, and wheel size.
Inputs
Results
Gear Ratio
2.941
How to Use This Calculator
- Enter your Chainring Teeth and Rear Cog Teeth.
- Set the Wheel Diameter (including tire) in millimeters and your Cadence in RPM.
- Review Gear Ratio, Speed in mph and kph, Gear Inches, and Development in meters per revolution.
- Check Skid Patches if you are riding a fixed-gear bike.
- Adjust chainring or cog size to find your ideal gear for climbing or sprinting.
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