What is the Stress Calculator?
Calculate axial, shear, bending, and torsional stress with this free stress calculator. Find normal stress σ = F/A, average shear τ = V/A, bending stress σ = My/I or σ = M/S, and maximum torsional shear τ = 16T/(πd³) on a solid round shaft. Optional yield strength gives safety factor and utilization. Metric (kN, mm², MPa) and imperial (lbf, in², psi) units with steel and aluminum yield presets. Runs instantly in your browser.
How to use the Stress Calculator
- Select stress type: axial, shear, bending (M/I/y or M/S), or torsion.
- Choose metric or imperial units.
- Enter force, area, moment, section properties, or torque and diameter as needed.
- Optionally enter yield strength or use a material preset for safety factor.
- Review stress in MPa or psi, utilization %, and calculation steps.
Common use cases
- Checking tensile stress in a steel rod under axial load
- Average shear stress in a bolt or pin connection
- Bending stress at the flange of an I-beam from moment and section modulus
- Surface shear stress on a drive shaft under torque
- Quick safety-factor check against A36 or A992 yield strength
Frequently asked questions
- What is normal (axial) stress?
- Normal stress σ = F/A is force divided by cross-sectional area. Tension is positive; compression uses the same magnitude formula. Units are MPa (N/mm²) or psi.
- How is bending stress calculated?
- Flexure formula σ = My/I gives stress at distance y from the neutral axis. Equivalently σ = M/S where S is the section modulus. Maximum stress occurs at the outermost fiber.
- What is the torsion formula for a solid shaft?
- Maximum shear stress at the surface of a solid circular shaft: τ = Tr/J = 16T/(πd³), where T is torque and d is diameter.
- What is safety factor?
- When yield strength is provided, safety factor = yield / calculated stress. Values above 1.0 mean stress is below yield (elastic). This is a simplified comparison — codes use additional factors.
- Is this average or peak shear stress?
- Direct shear τ = V/A is the average over the area. Peak shear in beams and connections can be higher; use appropriate section formulas or FEA for critical design.
