Shaft Stress & Torsion Calculator

Torsional shear stress, angle of twist and basic capacity check for a solid circular shaft under pure torque.

Shaft diameter d (mm)Applied torque T (N·m)Shaft length L (mm)Shear modulus G (GPa)Allowable shear stress (MPa), optionalCalculate

Equations

J = πd⁴/32 · τ = 16T/(πd³) · θ = TL/(JG)

Assumptions

Solid circular shaft, linear elastic torsion, uniform material properties, pure torque only (no combined bending).

Validation

Check keyways, shoulders, stress concentrations, fatigue and combined bending before design release.