Pulmonology Calculators
Respiratory tools — A-a gradient, FiO2 conversion, P/F ratio, oxygen tank duration, and the Asthma Control Test.
This category currently includes 9 tools, including FiO₂ Conversion, P/F Ratio, and O₂ Tank Duration.
These resources are built for clinicians, trainees, and medically informed patients who need fast bedside calculations. Use the results as decision support and pair them with full clinical context and local guidelines.
All Pulmonology Tools (9)
FiO₂ Conversion
Nasal cannula O2 flow (L/min) to FiO2%: quick chart for 1-6 L/min, e.g. 2 L/min ≈ 29% FiO2. Covers face mask, non-rebreather, HFNC, and P/F ratio inputs.
P/F Ratio
Calculate the P/F ratio to classify ARDS severity by Berlin criteria. Mild: 200–300 (27% mortality). Moderate: 100–200 (32%). Severe: <100 (45%). Normal P/F is 400–500.
O₂ Tank Duration
Estimate oxygen cylinder duration by tank size, PSI, and flow rate (L/min). Includes D, E, G, H/K, and M tanks for EMS transport, inpatient transfer, and home oxygen planning.
STOP-BANG
Screen for obstructive sleep apnea risk using the validated STOP-BANG questionnaire (0-8 points).
Pack-Year Calculator
Calculate pack-years from cigarettes per day and years smoked. Useful for documenting smoking burden and lung cancer screening discussions.
ACT Score
Calculate the Asthma Control Test score to assess asthma control over the past 4 weeks.
COPD GOLD
Classify COPD severity using 2024 GOLD spirometric stages (GOLD 1–4) and ABE exacerbation grouping. Guides inhaler step-up therapy, pulmonary rehabilitation, and oxygen therapy decisions.
mMRC Dyspnea Scale
Grade baseline breathlessness from 0 to 4 with the modified Medical Research Council (mMRC) dyspnea scale.
BODE Index
Estimate COPD mortality risk with the BODE index using BMI, airflow obstruction, dyspnea grade, and 6-minute walk distance.