# Strain Calculator

> Calculate strain step by step: ε = ΔL ÷ L₀ (dimensionless).

Page: https://freecalculator.tech/tools/strain-calculator
Last reviewed: 2026-11-03

## Formula

ε = ΔL ÷ L₀ (dimensionless).

- Use the same unit for both lengths.
- Negative change means shortening (compressive strain).
- Engineering strain based on original length.
- ε = ΔL ÷ L₀ (dimensionless).
- Inputs used: Original length, Change in length.

## Inputs

- Original length
- Change in length

## Worked example: 1 m bar stretches 0.5 mm

Tensile strain.
1. ε = 0.5 ÷ 1000 = 0.0005 (500 µε).

## Common questions

### Why does strain have no unit?

It is length divided by length, so units cancel. It is often shown as microstrain (×10⁻⁶).

### What is true strain?

True strain is ln(L/L₀) and matters for large deformations. For small strains it equals engineering strain.

### How do I get stress from strain?

In the elastic range, stress = Young's modulus × strain — see the Young's modulus calculator.

### How do I use the Strain Calculator?

Enter the required values for Original length, Change in length. The calculator applies the formula on this page and shows the main result with any supporting breakdown so you can check the arithmetic.

### What formula does the Strain Calculator use?

ε = ΔL ÷ L₀ (dimensionless). The visible formula section above lists the calculation path and the edge cases the page handles, so the result can be checked without relying on the form alone.

### Can the Strain Calculator be used for exact decisions?

Use it as a calculation aid, not as a substitute for checking the underlying rule, contract, policy, or professional advice that applies to your situation. When a result depends on local rules, personal details, prices, or dates, enter those values yourself and confirm them before acting.

## Limitations and assumptions

- Engineering (small) strain.
- Uniform deformation assumed.
- Thermal strain not separated.
- Results are estimates for planning and learning. Real designs, installations and bids must be checked by a qualified, licensed professional against the codes that apply where you work.
- The result depends on the values you enter for this strain calculator; it does not supply missing rates, rules, prices, dates, or assumptions for you.

## Sources

- OpenStax (Rice University) — https://openstax.org/details/books/university-physics-volume-1

## Cite this page

- APA: Free Calculator. (2026, November 3). Strain Calculator. https://freecalculator.tech/tools/strain-calculator
- MLA: "Strain Calculator." Free Calculator, 3 Nov. 2026, https://freecalculator.tech/tools/strain-calculator.
- Link: Strain Calculator — Free Calculator, https://freecalculator.tech/tools/strain-calculator