Stress & Strain Calculator
Engineering stress, strain and elongation of a bar under axial load.
A 20 mm steel bar under 50 kN runs at 159 MPa — 64% of Fe250 yield, stretching 1.6 mm per 2 m. Stress tells you about failure; strain about fit and function.
Formula
Stress & Strain Calculator is a free stress strain calculator for design engineers, metallurgists and QA inspectors — instant, accurate and 100% client-side, with the governing formula and reference shown next to the result so the number can be defended, not just quoted.
About Stress & Strain Calculator
Engineering stress, strain and elongation of a bar under axial load. The calculation implements σ = P/A; ε = σ/E; δ = εL = PL/AE (Hooke's law — any strength-of-materials text). A 20 mm steel bar under 50 kN runs at 159 MPa — 64% of Fe250 yield, stretching 1.6 mm per 2 m. Stress tells you about failure; strain about fit and function.
How to use Stress & Strain Calculator
- 1Enter Axial force in kN.
- 2Enter Cross-section area in mm² (20Ø bar = 314 mm²).
- 3Enter Original length in m.
- 4Enter Elastic modulus E in GPa.
- 5Read Stress, Strain, Elongation instantly — no submit button needed.
- 6Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Stress & Strain Calculator?
- ✓Implements the standard formula — σ = P/A; ε = σ/E; δ = εL = PL/AE
- ✓Reference cited on-page: Hooke's law — any strength-of-materials text
- ✓One-click SI ⇄ Imperial toggle — values convert in place, physics stays in SI
- ✓Live worked example: the substitution recomputes from your numbers
- ✓Runs entirely in your browser — nothing uploaded, free forever
Frequently asked questions
What formula does the Stress & Strain Calculator use?+
It computes σ = P/A; ε = σ/E; δ = εL = PL/AE, per Hooke's law — any strength-of-materials text. The formula is displayed under the result along with a worked example substituted with your own inputs.
What should I keep in mind when using this calculator?+
A 20 mm steel bar under 50 kN runs at 159 MPa — 64% of Fe250 yield, stretching 1.6 mm per 2 m. Stress tells you about failure; strain about fit and function.
Where do the material property defaults come from?+
Defaults are standard handbook values (ASM, manufacturer datasheets, the cited standard). Always substitute certified values from your material's test certificate for critical work.
Is the Stress & Strain Calculator free to use?+
Yes — completely free, no sign-up, no limits. It runs client-side in your browser, so inputs stay private and results are instant even on slow connections.
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