Gear Ratio Calculator
Calculate gear reduction from driving and driven tooth counts.
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What this tool does
Calculate gear reduction from driving and driven tooth counts. Ideal mechanical ratio; multiply ratios for multiple gear stages.
How to use the Gear Ratio Calculator
- Enter or select driven gear teeth.
- Enter or select drive gear teeth.
- Read the calculated result; change any measurement to compare alternatives.
Formula
gear ratio=driven teeth/drive teeth
- driven
- Driven gear teeth
- drive
- Drive gear teeth
Ideal mechanical ratio; multiply ratios for multiple gear stages.
Worked example
For gear ratio calculator, the following measurements illustrate the exact method: Driven gear teeth: 41; Drive gear teeth: 10.
Inputs
- Driven gear teeth41
- Drive gear teeth10
Result
- Gear ratio4.1
Results explained
- Gear ratio
- Gear ratio from the formula above. Ideal mechanical ratio; multiply ratios for multiple gear stages.
Frequently asked questions
gear ratio=driven teeth/drive teeth
Use the tire sidewall markings, actual vehicle specifications or recorded fuel/price values required by the inputs. Do not mix US gallons and imperial gallons.
Ideal mechanical ratio; multiply ratios for multiple gear stages.
Yes. Change the relevant size, price or efficiency while keeping the other inputs constant. Results update immediately.
No. Check manufacturer fitment, load and speed ratings, clearance and local requirements with a qualified technician.