PaO₂/FiO₂ Ratio Calculator

Free calculate PaO₂/FiO₂ ratio (P/F ratio). This is an educational tool only - always consult a healthcare provider.

Blood Gas Values

Enter as decimal (e.g., 0.4 for 40%)

Results

Enter blood gas values to calculate P/F ratio

About P/F Ratio

  • • P/F Ratio = PaO₂ / FiO₂
  • • Normal: >400
  • • Mild ARDS: 200-300
  • • Moderate ARDS: 100-200
  • • Severe ARDS: <100
  • • Used in ARDS classification