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Gear Train Ratio

Overall ratio = product of (driven ÷ driver) across stages. Speed divides by the ratio, torque multiplies by it (less efficiency losses). For single-pair geometry use the spur gear tool.

Stages

Stage	Driver teeth	Driven teeth	Ratio

Input speed (rpm)

Input torque (N·m)

Efficiency per stage

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Output speed

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Output torque

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Overall efficiency

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A helper, not a substitute for engineering judgment.