GearTrain
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Teeth · stages · rotational speed

Keep every gear stage in one exact ratio.

GearTrain solves ideal external-gear kinematics locally. It does not design, rate, or approve the gears.

Calculated in this browser

Gear train

No gear data leaves this device
Stage 1
Leave blank to calculate ratio only.

Each stage is one external mesh. Verify module, pitch, geometry, strength, speed limits, and safety separately.

Ideal kinematic result

Combined gear train

Total ratio i · Speed reduction3:1Exact reduced value: 3
Output speed factor×≈0.333333Exact reduced value: 1/3
Ideal output speed600 RPM
Output directionOpposite to input

Stage ratios

Stage 136/12 = 3:13

i = 36/12 = 3

The fraction remains exact. An approximation mark appears only when a displayed decimal is rounded.

Ratio arithmetic does not prove that gears mesh, fit, carry load, or run safely. Use current engineering data for the real mechanism.