Beam Bending & Stress Simulator
Move a load along a beam, see deflection, the bending moment diagram and whether it stays safe.
Choose how the beam is supported, the load on it, the material and the shape of its cross-section. Drag the red load arrows along the beam. See the deflection, the shear force and bending moment diagrams, the stress colours and the reactions update instantly, and hover along the beam to read values at any point.
About the Beam Bending & Stress Simulator
Free beam bending & stress simulator. Move a load along a beam, see deflection, the bending moment diagram and whether it stays safe. Drag, change the sliders and see the result live. No sign-up, works on phone and computer. Built for engineering, the beam bending & stress simulator runs instantly in your browser: change a setting or drag an object and the result updates at once, so you learn by trying things out rather than only reading about them.
Move a load along a beam, see deflection, the bending moment diagram and whether it stays safe. Use it to explore engineering ideas at your own pace, then check what you found against the key ideas further down this page.
How to use the Beam Bending & Stress Simulator
- Use the controls to change Supports, Load, Beam length, Point load, Distributed load, and more. The simulation reacts instantly.
- Pick an option such as Simply supported, Cantilever (fixed), Fixed both ends, Fixed + roller to switch modes or load an example.
- Press "Overload it!", "Reset" to start, reset or change what is happening.
- Where you see a glowing handle, object, weight or atom, drag it with your mouse or finger. Everything responds in real time.
- Watch the readouts and graphs update as you experiment, and compare what you see with the key ideas below.
Things to try
- Compare steel and timber.
- Double the beam height.
- Switch to a cantilever and move the load to the tip.
Key ideas you can learn
- Deflection depends on load, length, material stiffness E and the second moment of area I.
- A deeper beam is much stiffer because I = b h³ / 12.
- The bending moment is largest under or near the load.
- A beam fails when stress exceeds the yield strength.
Where this is used in the real world
Floors, bridges, aeroplane wings and shelves are all beams sized with these equations.
Who is this simulation for?
Engineering and technology students, makers, robotics clubs and teachers of design and technology. It gives a hands-on feel for how machines behave before you build a real one.
For teachers: project it on the board, let students predict what will happen, then run it together. For students: change one thing at a time and write down what changes.
Frequently asked questions
Why are beams tall and thin?
Stiffness grows with the cube of the height, so a tall beam bends much less for the same material.
What is a cantilever?
A beam fixed at one end only, like a diving board.
Is the Beam Bending & Stress Simulator free to use?
Yes. It is completely free, with no signup, no download and no ads inside the simulation. It runs in your web browser.
Does the Beam Bending & Stress Simulator work on a phone or tablet?
Yes. It uses touch as well as the mouse, so you can drag objects with your finger. A larger screen makes the controls easier to see.