Quick shaft diameter sizing from transmitted power and speed, for pure torsion (no significant bending).
Shaft Diameter Calculator
Inputs
Results
- Torque
- 66.31N·m
- Minimum Diameter
- 20.03mm
- Recommended Standard Size
- 22mm
Formula Used
⚠ For preliminary design and educational use only. Verify all results against applicable codes and standards before use in production or safety-critical applications.
About this calculator
Part of our Mechanical Calculators collection. Beams, bolts, springs, gears, bearings, and core ME calculations.
How it works
Determines the minimum shaft diameter needed to transmit a given power at a given speed, based on allowable shear stress under pure torsion.
Enter your values in the inputs above and click CALCULATE. Results appear on the right without a page reload. No login and no server upload.
Privacy and accuracy
Every calculation runs locally in your browser. Your design data never leaves your device. Results are intended for preliminary engineering work. Always verify critical designs with qualified review and applicable standards before production use.
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