Linear Thermal Expansion Calculator
Estimate signed length change, final length and relative expansion from temperature change.
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Estimate unconstrained length change with temperature
Enter initial length, a linear expansion coefficient in micrometers per meter-kelvin and a signed temperature change. The page reports length change in millimeters, final length and relative change as a percentage. These connected outputs make the coefficient scale visible and support early checks for rails, frames, shafts, panels and laboratory specimens.
Account for constraints and material behavior
The calculation assumes a constant coefficient, uniform temperature and free expansion along one dimension. Fasteners, joints and temperature gradients can create stress instead of allowing the full movement. Composite or anisotropic materials may expand differently by direction. Use material data over the actual range and a structural method when clearance, buckling, seals or safety depend on the result.
Frequently asked questions
Can temperature change be negative?
Yes. A negative change usually produces contraction for a positive coefficient.
Why is the coefficient entered in micrometers?
That common scale avoids typing very small decimal coefficients.
Does the tool calculate thermal stress?
No. Stress depends on constraints, stiffness, geometry and boundary conditions.