Dalton Triangle

Dalton's Law says the partial pressure of a gas equals the fraction of that gas times the ambient pressure: PO₂ = FO₂ × P. Underwater, P is the absolute pressure from depth plus 1 bar of surface pressure (adjusted by water type). This tool lets you choose which value to compute (PO₂, FO₂, or Depth), enter the other two, and get the answer instantly.