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Solve, convert and look up in the browser
EngiRef tools are free browser calculators for engineering work: a unit converter covering 134 units, a physical constants lookup and formula solving. Everything is computed in your browser with no account, and any result can be saved to your calculation history and exported.
Formula solver
Stress is force per unit area acting on a material
Every other variable is taken from the fields above; σ is what is being solved for.
\sigma = \frac{F}{A}
Constants lookup
Speed of Light in Vacuumc = 299792458 m/s
Planck Constanth = 6.62607e-34 J·s
Reduced Planck Constantℏ = 1.05457e-34 J·s
Elementary Chargee = 1.60218e-19 C
Avogadro's ConstantNᴀ = 6.02214e+23 1/mol
Gravitational ConstantG = 6.6743e-11 N·m²/kg²
Fine Structure Constantα = 0.00729735257
Vacuum Permittivityε₀ = 8.85419e-12 F/m
Formula references
The twelve most-reached-for equations. All 119 are in the formula library.
Normal Stress\sigma = \frac{F}{A}
Normal Strain\varepsilon = \frac{\Delta L}{L_0}
Hooke's Law\sigma = E \varepsilon
Shear Stress\tau = \frac{V}{A}
Torque\tau = F \cdot r
Moment of Inertia (Rectangle)I = \frac{bh^3}{12}
Moment of Inertia (Circle)I = \frac{\pi d^4}{64}
Newton's Second LawF = ma
Kinetic EnergyKE = \frac{1}{2}mv^2
Gravitational Potential EnergyPE = mgh
Power (Work/Time)P = \frac{W}{t}
Power (Rotational)P = \tau \omega