Beam Deflection Calculator

Calculate deflection, bending moment, and shear force for structural beams.
The force applied to the beam.
mm
MPa
Steel ~ 200,000 MPa, Wood ~ 10-15,000 MPa
mm⁴
Area Moment of Inertia of the cross-section.
Calculate Moment of Inertia (Rectangle)
Formula: (b * h³) / 12
mm
Maximum Deflection
Slope (Theta) at Support rad
Max Bending Moment

* Calculations assume linear elastic behavior.
* Simply Supported (Point): P*L³ / 48EI
* Simply Supported (UDL): 5*w*L⁴ / 384EI (Note: here W is total load = w*L) -> 5*W*L³ / 384EI
* Cantilever (Point): P*L³ / 3EI
* Cantilever (UDL): w*L⁴ / 8EI -> W*L³ / 8EI

Features

  • Beam Deflection Analysis: Calculate deflection for common beam configurations.
  • Support for Load Units: Input loads in N, kN, or kg.
  • Moment of Inertia Helper: Built-in calculator to find 'I' for rectangular sections.
  • Multiple Beam Cases: Covers Simply Supported and Cantilever beams with Point or Distributed loads.

How to Use

  1. Select the Beam Type (e.g., Simply Supported or Cantilever).
  2. Enter the Load value and select the unit.
  3. Input the Beam Length in mm.
  4. Enter Young's Modulus (E) and Moment of Inertia (I). Use the helper if you have a rectangular section.
  5. Maximum deflection is calculated instantly.