Bolt head types guide
Fasteners
Compare hex, socket head, button head, and countersunk bolts for design, assembly, and service access.
Calculator tabs
Doc version: 1.0 | Updated: 2026-02-07
CalculatorFree
Shaft Torsion
Compute torsional stress and twist angle from torque and shaft size.
Inputs
Enter torque, geometry, and material.
Results
Shear stress, twist angle, and safety factor.
Shear stress tau
47.16 MPa
Twist angle theta
1.801 deg
Safety factor
-
How it is calculated
Formulas used
tau = 16T / (pi * d^3)
theta = T * L / (J * G)
J = pi * d^4 / 32
Variables
- T
- Applied torque.
- d
- Shaft diameter.
- L
- Shaft length.
- G
- Shear modulus.
- J
- Polar moment of inertia.
- tau
- Shear stress.
- theta
- Twist angle.
Usage notes
- Assumes a solid circular shaft.
- Elastic behavior and small angles are assumed.
Show reports, charts, and comparison tools
After checking the basic result, open sharing, PDF, method notes, and comparison panels.
Standard Documentation
Shaft TorsionScope: What does this tool calculate?
Shaft Torsion performs the core engineering calculation for this tool type and presents results in a traceable format.
Assumptions and Units
- SI units are the baseline; input unit consistency must be verified by the user.
- The calculation path is deterministic (same inputs = same outputs).
- If default material/environment values are used, replace them with project-specific values.
Limits / Boundaries
- This tool is intended for preliminary sizing and technical checks, not final design approval.
- When inputs are outside expected ranges, validate input quality before interpreting outputs.
Reference Standard
- ISO / DIN / VDI references and common engineering handbooks
Validation Example
Validation example
| Input | Expected Output |
|---|---|
| Input set: Unit-consistent project values | Expected output: Tool result is in the same order as standard references |
Note: In real projects, run at least one manual check or reference-table comparison.
Version and Update
- Version
- v0.1.0
- Last updated
- 2026-03-04
Premium beta
Premium plan
Premium is in private beta. Early access opens in small batches.
Calculation explanation
How to use
- Enter torque, diameter, length, and shear modulus.
- Add allowable shear stress if you have a limit.
- Check shear stress, twist angle, and safety factor.
Formula
τ = 16·T / (π·d^3) | J = π·d^4/32 | θ = (T·L)/(J·G)Common mistakes
- Entering diameter in meters instead of mm.
- Using G in MPa instead of GPa.
- Mixing length units (mm vs m).
References
- Shigley's Mechanical Engineering Design — Torsion stress and twist formulas.
Confidence SnapshotVersion: 1.0
Last updated: 2026-02-07
References
- Shigley's Mechanical Engineering Design — Torsion stress and twist formulas.
Assumptions
- Circular, uniform cross-section.
- Linear elastic behavior.
Guides
Related guides
Browse guides with similar tags.
Glossary
Related terms
Terms that share the same concepts as this calculator.
Coefficient of Friction
Mechanical
Coefficient of Friction is a core engineering term. Definition, usage notes, and a practical example.
Shear Stress
Mechanical
Shear Stress is a core engineering term. Definition, usage notes, and a practical example.
Torque
Mechanical
Torque is a core engineering term. Definition, usage notes, and a practical example.
Bending Moment
Mechanical
Bending Moment is a core engineering term. Definition, usage notes, and a practical example.
Similar calculators
Related calculators
Explore calculators with similar categories or tags.
Bolt Size & Torque
Free
Calculate stress area and preload from nominal diameter, pitch, and grade.
Spring Force Chart
Free
Generate an F-x chart from spring constant and displacement.
Tensile Stress
Free
Compute tensile stress from force and cross-section area.
Bending & Deflection
Free
Bending stress and max deflection for a simply supported beam.
Other picks
These might help too
Review alternative calculators for adjacent needs.
Power - Torque - RPM
Free
Compute torque or power from kW, hp, and rpm.
Gear Design
Free
Overview and entry point for gear design calculations.
Gear Force & Torque
Free
Compute gear torque and transmitted forces.
Unit Converter
Free
Fast unit conversions for length, force, pressure, and energy.