Bicycle Gear Ratio Calculator
Estimate bicycle gear ratio and gear inches.
Inputs
Bicycle Gear Calculator
Results update as you type.
Live result
Gear ratio
2.94
Gear inches
79.41
Scenario compare
Save scenario A, change a few inputs, then save scenario B.
Scenario A
Not saved yet
Scenario B
Not saved yet
Quick check
Change one or two inputs to compare a second scenario before using the number.
Need more detail?
Formula, examples, and FAQ stay tucked away until you need them.
FXFormula ExplanationThe core logic behind the numbers on this page.+
Our bicycle gear calculator uses a transparent arithmetic formula to estimate the gear ratio and gear inches based on the inputs provided. The formula takes into account the number of teeth on the front and rear sprockets, the chainring size, and the wheel size. The result is an estimate of the gear ratio and gear inches, which can be used to plan your bike's gearing for a smooth and efficient ride.
USEHow to UseA short path from input to result.+
- Enter the requested inputs.
- Keep any editable rule or rate fields aligned with your situation.
- Review the result and notes before using the estimate.
EXExamplesReference scenarios to sanity-check your inputs.+
Adjust the defaults to match your scenario, then calculate the estimate.
FAQFAQCommon edge cases and quick clarifications.+
What is gear ratio and why is it important?
Gear ratio refers to the ratio of the number of teeth on the front sprocket to the number of teeth on the rear sprocket. A higher gear ratio can make pedaling easier, but may make climbing hills more difficult. A lower gear ratio can make climbing hills easier, but may make pedaling more difficult.
How do I adjust the assumptions in the calculator?
You can adjust the editable rate and rule fields in the calculator to match your specific situation. This may include adjusting the chainring size, wheel size, or other factors that affect the gear ratio and gear inches.
Is this calculator accurate?
This calculator provides an estimate of the gear ratio and gear inches based on the inputs provided. While it can be a useful planning tool, it is not a substitute for official or current rules and regulations.
What are gear inches?
Gear inches is a measure of the difficulty of pedaling a bicycle. A higher gear inch value indicates a more difficult ride, while a lower gear inch value indicates an easier ride.
Can I use this calculator for my specific bike?
Yes, you can use this calculator to estimate your gear ratio and gear inches for your specific bike. Simply enter the details of your bike, including the number of teeth on the front and rear sprockets, the chainring size, and the wheel size.