Bolt Size & Torque
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Calculate stress area and preload from nominal diameter, pitch, and grade.
Tool report
Gear Ratio Calculator
Calculate ratio, output speed, and torque from tooth counts and input speed.
DateMay 15, 2026
Inputs
Input tooth count z120
Output tooth count z260
Input speed n1 (rpm)1,500 rpm
Input torque T1 (Nm)50 Nm
Efficiency η0.97
Results
Ratio3
Rpm2500
Torque2145.5
Efficiency0.97
Formula
i = z2 / z1 | n2 = n1 / i | T2 = T1 * i * η
Assumptions
- Ideal gear ratio; backlash and elasticity are neglected.
- Efficiency ? is represented by a single factor.
References
- AGMA 2001 (Fundamental gear design)
- ISO 6336 (Cylindrical gears)
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