basic

Factor of Safety from Yield and Applied Stress Calculator

FOS = σ_yield / σ_applied — design safety margin.

Calculates factor of safety FOS = σ_yield / σ_applied. FOS < 1 → failure; 1.5 = minimum structural; 3+ = critical safety. Also computes allowable stress = σ_yield / required_FOS.

Daniel Oh By Daniel Oh
Published Last reviewed 1 min read

Inputs

Pa
Pa

Results

Enter values and click Calculate to see results.
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How to use this calculator

  1. Fill in the inputs above using the units you already have.
  2. Values update automatically as you type — no submit button needed.
  3. Hover any result row for the underlying formula and intermediate values.

Formula

FOS = σ_yield / σ_applied; σ_allow = σ_yield / FOS_req

In depth

Calculates factor of safety FOS = σ_yield / σ_applied. FOS < 1 → failure; 1.5 = minimum structural; 3+ = critical safety. Also computes allowable stress = σ_yield / required_FOS.