Auto
Gear Ratio Calculator
Gear ratio from driven and drive tooth counts, output RPM, and torque multiplication.
Inputs
Gear Ratio Calculator
Result
Gear ratio
3 : 1
- Output RPM
- 1,000
- Torque multiplication
- 3×
How it's calculated
ratio = driven / drive; output RPM = input RPM / ratio; torque out = torque in × ratio
Common questions
Is a higher gear ratio better?
It depends. A higher (numerically larger) ratio multiplies torque and lowers output speed — good for climbing or acceleration. Lower ratios trade torque for top speed and efficiency.
How does gear ratio affect torque?
Ignoring losses, output torque equals input torque multiplied by the gear ratio, and output RPM equals input RPM divided by the ratio.
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