Bike Gear Calculator
Estimate gear ratio, gear inches, and rollout from chainring size, rear cog, and wheel diameter.
Estimate Bike Gearing
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Bike gear calculator guide
WeCovr's bike gear calculator estimates gear ratio, gear inches, and rollout from chainring size, rear cog, and wheel diameter.
What this bike gear calculator does
This page compares gearing by converting chainring and rear cog sizes into practical reference numbers.
Returns gear ratio.
Returns gear inches.
Returns rollout per crank revolution.
Why cyclists compare gears
Comparing gears helps riders understand how far the bike travels per pedal stroke and how different setups may feel on climbs or fast sections.
What the calculator simplifies
Real ride feel also depends on cadence, terrain, tyre size, rider strength, and how the bike is actually used under load.
Cycling setup tools
| Tool | Focus | Typical use |
|---|---|---|
| Bike gear | Mechanical ratio | Setup comparison |
| Bike cadence | Pedalling rate | Ride planning |
| Bike pace | Speed and pace | Performance review |
Related WeCovr resources
FAQs
What is gear ratio?
It is the number of chainring teeth divided by the number of rear-cog teeth.
Why use gear inches?
Gear inches are a traditional way to compare how large or small a bike gear feels.
Does rollout matter more than ratio?
Rollout can be more intuitive because it estimates distance traveled per crank revolution.
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