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.
How the result changes with Rear Cog Teeth
| Rear Cog Teeth | Gear Ratio |
|---|---|
| 13 | 3.846 |
| 24 | 2.083 |
| 37 | 1.351 |
| 48 | 1.042 |
What each input means
- Chainring Teeth
- Number of teeth on the front chainring. Common road: 34-53, MTB: 28-38.
- Rear Cog Teeth
- Number of teeth on the rear sprocket/cog. Common road: 11-34, MTB: 10-52.
- Wheel Diameter (with tire)
- Overall wheel diameter including the inflated tire. A 700x25c tire is approximately 700mm.
- Cadence
- Pedaling cadence in revolutions per minute. Typical: 80-100 rpm.
Engine last updated .
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