Shear & Moment Diagram Calculator

A free shear force and bending moment diagram calculator (SFD and BMD) that runs in your browser, with no sign-up. Build a beam, and it draws the support reactions, the shear force diagram, the bending moment diagram and the deflection, with the key values labelled.

How to use it

1. Pick a template, from a simply supported beam to a four-span continuous beam, or start with the empty beam.
2. Click or drag "Pin", "Roller", "Fixed" or "Hinge" and the loads "Point load", "Moment", "UDL" or "Linear load" onto the beam.
3. Click an item to edit its numbers, drag it along the beam, or drag the ↔ handle under a span to change its length.
4. Read the reactions, V and M, and open the step-by-step solution for the hand calculation as formulas.

What it covers

• Statically determinate and indeterminate beams: simply supported, cantilever, overhanging, propped, fixed–fixed, continuous and Gerber beams with internal hinges.
• Point loads, point moments, uniform and linearly varying (triangular or trapezoidal) loads.
• SI units (kN, m) and US units (kip, ft); the moment diagram drawn with +M up or on the tension side.
• Export as SVG, PDF (vector), PNG or JPG, and a link that reopens the same beam.

The model is a straight horizontal Euler–Bernoulli beam with one EI. E and I only change the deflection: with constant EI they do not change the reactions, V or M, also for indeterminate beams. The solver is tested against the beam tables of Schneider Bautabellen für Ingenieure, worked examples from Hibbeler's Structural Analysis, an exact solution of about 445 beams and the open-source FEM program anaStruct.

Learn the method by hand in the guideShear and Moment Diagrams: How to Draw SFD and BMD, with seven worked examples. To sketch a free body diagram first, use Statics Sketcher.