PaO₂/FiO₂ (P/F) Ratio Calculator
mmHg
= 10.7 kPa
kPa
= 80 mmHg
%
= 0.40
mmHg
kPa
Normal oxygenation
Normal: > 300 mmHg (> 40 kPa)
Mild ARDS: 200–300 mmHg (26.7–40 kPa)
Moderate ARDS: 100–200 mmHg (13.3–26.7 kPa)
Severe ARDS: <= 100 mmHg (<= 13.3 kPa)
Berlin Definition classification shown; formal ARDS diagnosis also needs acute onset, bilateral opacities, and PEEP/CPAP ≥ 5 cm H₂O.
Enter PaO₂ in mmHg or kPa (both sync). FiO₂ is set as a %; fraction shown automatically.