Gear Strength Calculator: Power & Strength Calculation for Gear Teeth

Calculating Power & Strength of Gears

  • This gear strength calculator uses gear geometry, material, and manufacturing methods to provide guidance on gear strength tooth. This lets you understand the maximum horsepower you can transmit through a gear.

Input your gear specifications in the light gray sections below, and use the dark gray sections to make adjustments based on your specific application. Gear strength equations are listed below the calculator, and all calculations conform to Dudley, Darle W. Gear Handbook: The Design, Manufacture, and Application of Gears. McGraw-Hill Book Company, 1962.


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How to Calculate Gear Strength?

A gear's strength or power rating is calculated from the:

  • speed of the pinion
  • module, pressure angle, and tooth count of the gear and pinion
  • pinion material (and its hardness)
  • method of manufacturing
  • face width and support conditions
  • power source and load conditions
  • material interaction between gear and pinion
  • total lifecycles
  • application requirements
  • and factors for temperature, hardness, surface condition, and size

Gear Strength Formula

It takes a lot of parameters to calculate the strength of gears. This equation combines the geometry, use case, and historical experience (from Dudley's 1962 Gear Handbook) to approximate the total allowable power:


Dudley's Handbook of Practical Gear Design and Manufacture (1962)

This calculator conforms to the standards in D.W. Dudley's Gear Handbook, an essential reference in gear design. The Gear Handbook is a hefty tome at over 800 pages of gear knowledge and information. What sets it apart is Dudley's emphasis on being practical, not just academic. By using empirical data, field observations, and real-world experience, Dudley effectively communicates useful information to those who need it.

Strength Calculator for Max Horsepower Through a Gear

The calculator will tell you the maximum power that you can transmit through a gear, in horsepower. This should be taken only as an approximate guide, and not a design parameter. While we've taken care to ensure numerical accuracy and agreement with the established methods, these general methods can't fully consider the specifics of your situation. If you need a more refined analysis, contact us and our engineers can work with you and your application.

Strength Analysis of Gears

Calculating ths strength of gears requires a mix of engineering, design, and metallurgy. We've had decades of experience working with gears and if you need a more refined analysis, contact us and our engineers can work with you and your application.

Gear Strength Calculators:

› Input gear parameters

› Input application details

› Calculate gear strength in horsepower