Factor of Safety Calculator

Calculate factor of safety, margin of safety and utilization from capacity (strength) and applied load or stress.

Calculate

Capacity (failure load, strength or rating)

Any unit — use the same unit for both values.

Applied load / stress

Required factor of safety (optional)

Formula

FoS = capacity ÷ applied; margin of safety = FoS − 1; utilization = applied ÷ capacity