PPolySim OS

Shear & Moment Diagrams

The two diagrams every structural engineer draws first. Add a point load and a distributed load and watch the shear and bending-moment diagrams redraw instantly.

Shear & Moment DiagramsLive

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Presets

Shear and bending-moment diagrams show the internal forces along a beam. Shear jumps at each point load; the moment is the running integral of shear and peaks where shear crosses zero. Engineers size beams for this maximum moment. Educational tool, not a substitute for structural design.

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Data Inspector

Reaction A28.3 kN
Reaction B21.7 kN
Max moment46.6 kN·m
at x2.01 m

Governing equation

Reading this result: Combined loading: reactions RA=28.3 and RB=21.7 kN, and the maximum moment 46.6 kN·m lands at x=2.0 m where shear crosses zero.

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How it works

Shear and bending-moment diagrams trace the internal forces along a beam. Shear jumps at each concentrated load, and the bending moment is the running integral of shear, peaking where shear passes through zero. Beams are sized for that maximum moment. Educational tool, not a substitute for structural design.

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Frequently asked questions

Is this shear moment diagram calculator tool really free?
Yes. Shear & Moment Diagrams runs entirely in your browser using your device's own compute, so local use is free forever. You only pay Compute Tokens if you scale a job to the cloud.
Do I need to install anything?
No. Everything runs client-side in a modern browser — no downloads, no license, no account required to start.
Can I save or share my simulation?
Create a free account to save projects, and use a shareable embed or minted DOI to publish a live, interactive version anywhere.
How accurate are the results?
The solver uses established numerical methods, but results are for research and educational purposes and should be validated against experiment or professional review before you rely on them.