Shear Force Calculator

Calculate beam shear force, maximum shear, support reactions, point load shear, uniform load shear, cantilever shear, and simplified shear stress. Use this shear force calculator for beams, joists, rafters, headers, cantilevers, deck beams, floor beams, and preliminary structural planning.

Calculate Shear Force

Shear force is the vertical force crossing a section. For a simply supported beam, reactions come from equilibrium and maximum shear is usually near a support.
Your result will appear here.

How the shear force calculator works

Support reactions:
The calculator uses static equilibrium to estimate left and right reactions for simply supported beams.

Maximum shear:
The calculator compares the absolute support reactions and section shear values to estimate controlling shear demand.

Uniform loads:
A full-span uniform load is converted into total load and split between supports for simple beams.

Shear stress:
The calculator divides shear force by shear area to estimate simplified average shear stress.

Why use a shear force calculator?

A shear force calculator helps estimate vertical shear demand before checking beam size, web area, allowable shear stress, support bearing, or connections.

It can help compare support reactions, maximum shear, shear at a section, cantilever shear, shear stress, shear capacity, and simplified utilization.

What your result means

Your result shows estimated left reaction, right reaction, maximum shear, shear at the selected section, total load, shear stress, allowable shear stress, shear capacity, and simplified shear utilization. These are preliminary planning estimates only.

Shear force formulas

Frequently asked questions

What is shear force?

Shear force is the internal vertical force that acts across a section of a beam or member. It helps determine whether the beam web, wood section, fasteners, or support area can resist the load.

Where is maximum shear in a simply supported beam?

Maximum shear is usually at or near one of the supports. For a centered point load or a full uniform load, the maximum shear equals half the total load.

How is shear different from bending moment?

Shear is an internal force, while bending moment is a turning effect. A beam usually needs both shear and bending checks.

Can this calculator design a beam?

No. This calculator estimates shear and simplified shear stress only. Final beam design should also check bending moment, deflection, bearing, lateral bracing, connections, load combinations, material properties, and local code requirements.