Enter each external pair
Name driver and driven teeth in motion order.
Teeth · stages · rotational speed
Turn every gear stage into one exact answer.
GearTrain multiplies one to four external gear pairs as reduced integer fractions, then derives ideal speed and direction without a parts database.
Tooth counts and RPM stay in this browser. Verify geometry, load, speed limits, and safety separately.
Three transparent steps
Describe the stages, reduce the fraction, read ideal motion
Keep one exact fraction
Ratios are multiplied and reduced before display.
Separate motion from design
Check compatible geometry, load, speed, and guarding elsewhere.
One bounded kinematic tool
Useful for checking a gearbox sketch before deeper design
- Confirm which way to divide driver and driven teeth.
- Combine up to four compound stages without intermediate rounding.
- Translate a known input RPM into ideal output speed.
- Check same or opposite output direction from mesh parity.
Keep every stage exact
Combine the tooth-count ratios in GearTrain
Enter one to four external gear pairs. GearTrain reduces the complete fraction before it displays ratio, speed factor, output RPM, and direction.