Beam Deflection Calculator

Calculate beam deflection, shear, and bending moment with diagrams

Beam Configuration

Beam Type

Load Type

Material

Young's Modulus

GPa

Cross-Section

Beam Section

Moment of Inertia (X-axis)

mm⁴

Input

Beam Length

Point Load

How to use Beam Deflection Calculator

1Select the beam support condition: cantilever, simply supported, or fixed ends.
2Enter beam length, load magnitude, load position, and material properties like Young's modulus and moment of inertia.
3Review the maximum deflection, reaction forces, and bending moment diagram summary.

Max deflection depends on load case; common case: δ_max = P × L^3 / (48 × E × I) for center point load

Beam deflection describes how much a structural member bends under applied loads without permanent deformation.

The deflection depends on load type, support conditions, span length, material stiffness, and cross-section shape.

Staying within allowable deflection limits prevents cracks in finishes and ensures serviceability.

What is allowable deflection?

Typical limits range from L/180 to L/360 of the span, depending on the building code and use.

Does this calculator replace structural engineering review?

No; it is an educational tool. Real designs require code checks for strength, stability, and safety factors.

Can I combine multiple loads?

Yes by superposition: calculate deflection for each load case and add the results if the system remains elastic.