Strain Calculator
Calculate engineering strain from the change in length and original length, with percent and microstrain.
How it works
- 1Enter the change in length (ΔL) and the original length (L).
- 2The calculator applies ε = ΔL ÷ L, a dimensionless ratio.
- 3Read the strain as a decimal, a percentage, and in microstrain (µε).
Use cases
- Interpreting strain-gauge readings in a test or experiment.
- Checking elongation against a material’s elastic limit.
- Working through stress–strain problems alongside Young’s modulus.
Frequently asked questions
What is engineering strain?
Engineering strain is the change in length divided by the original length: ε = ΔL ÷ L. It is dimensionless. A 0.5 mm stretch over 1000 mm is a strain of 0.0005.
What is microstrain?
Microstrain (µε) is strain × 10⁶, a convenient unit for the very small strains measured by strain gauges. A strain of 0.0005 equals 500 µε.
How does strain relate to stress?
In the elastic region they are proportional through Young’s modulus: stress = E × strain. Strain describes the deformation; stress describes the internal force causing it.
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