Shear Force Diagram Calculator
Work out shear force diagram instantly with clear inputs, formula shown and shareable results.
About Shear Force Diagram Calculator
For an off-centre point load, taking moments about each support splits the load in inverse proportion to the distances: the near support takes more. A 9 kN load 2 m along a 5 m span puts 5.4 kN on the left support and 3.6 kN on the right. The shear diagram is constant at each reaction value and jumps by the load at its position, so peak shear is the larger reaction.
Formulas
Support reactions
R(right) = P a / L, R(left) = P - R(right)
Moment under the load
M = R(left) x a
Worked example
With the default values below, Shear Force Diagram Calculator returns Maximum Shear Force of 5,400.0. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Point loadminimum 0 N
- 9,000 N
- Span between supportsminimum 0 m
- 5 m
- Distance of the load from the left supportminimum 0 m
- 2 m
Results
- Maximum Shear Force
- 5,400.0 N
- Left Support Reaction
- 5,400.0 N
- Right Support Reaction
- 3,600.0 N
- Bending Moment Under The Load
- 10,800.0 N m
Step by step
- 1Values used
- 2Support reactions
- 3Moment under the load
- 4Maximum Shear Force= 5,400.0 N
- 5Left Support Reaction= 5,400.0 N
- 6Right Support Reaction= 3,600.0 N
- 7Bending Moment Under The Load= 10,800.0 N m
Assumptions and limits
- The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax or compounding frequency into account.
- Figures are rounded for display to 1 decimal place, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
Where is the shear force greatest?
Immediately beside the support with the larger reaction, which is the support nearer the load.
Why does the diagram jump at the load?
Because a point load is an abrupt change in the internal force. Distributed loads give sloping shear diagrams instead of steps.