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Thermal Expansion Calculator

Find how much a material expands when heated, from its length and coefficient of thermal expansion.

Inputs

Saved Scenarios

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Length Change (mm)

6.00

Spark says

How it's calculated

Formula

ΔL=L×α×ΔT\Delta L = L \times \alpha \times \Delta T
L
— Original length
\alpha
— Coefficient of linear thermal expansion
\Delta T
— Temperature change

What is the Thermal Expansion Calculator?

Most materials expand when heated and contract when cooled, roughly proportional to their original length, the temperature change, and a material-specific expansion coefficient — a key consideration for expansion joints in bridges, railways, and pipelines.

How to use it

  1. 1 Enter the material's original length.
  2. 2 Choose the material (or enter its known expansion coefficient).
  3. 3 Enter the expected temperature change.

Worked examples

Limitations

  • This is linear expansion along one dimension — for large temperature swings or precision work, expansion coefficients themselves vary somewhat with temperature.

Frequently asked questions

Why do bridges have expansion joints?

A long bridge deck can change length by several centimeters between summer and winter — expansion joints absorb this movement so the structure isn't forced to buckle or crack.