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Euler column buckling-load calculator.

Estimate ideal elastic critical load, slenderness, and a first-pass stability utilisation for a prismatic column.

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Stability depends on stiffness and effective length.

Euler buckling is an ideal elastic instability model. It turns flexural stiffness, second moment of area, and effective length into a critical axial load, while radius of gyration makes the same geometry visible as slenderness.

Governing relationships

The ideal critical load is Pcr = π2EI/(KL)2. The radius of gyration is r = √(I/A), and the screened slenderness is KL/r. The tool compares the entered compression with Pcr only as an elastic reference.

What still needs a full column design

  • Real columns include imperfections, residual stress, eccentricity, material nonlinearity, second-order effects, connection restraint, and load-duration effects.
  • Check the applicable code's buckling curves, slenderness limits, load combinations, resistance factors, local buckling, fire, and durability requirements.
  • Use I, A, and K about the same buckling axis. A larger strong-axis value does not protect a weaker-axis failure.