Peak Expiratory Flow Rate (PEFR / PEF) & Asthma Action Zones Calculator
Calculate your predicted normal Peak Expiratory Flow (PEF in L/min) using the European standard (Nunn & Gregg equations) from age, sex, and height, and determine your personal Asthma Green, Yellow, and Red traffic light action zones.
Predicted Normal Peak Flow (L/min)
Calculator Inputs
Predicted Normal Peak Flow (L/min)
Measured PEF Percentage of Predicted (%)
Green Zone Safe Threshold (80% in L/min)
Measured PEF vs Predicted Normal PEF (Liters/minute)
Respiratory clinical monitoring tool for Asthma and COPD management endorsed by the Global Initiative for Asthma (GINA) and ERS.
This tool is a mathematical wellness and fitness estimation model for general educational guidance only. The results do not constitute medical diagnosis, clinical advice, or treatment plans. Always consult a qualified physician or certified dietitian before starting any dietary regimen, exercise program, or making health decisions.
Calculation Methodology
Men: Predicted PEF = [((Height_m * 5.48) + 1.58) - (Age * 0.041)] * 60. Women: Predicted PEF = [((Height_m * 3.72) + 2.24) - (Age * 0.030)] * 60. Green Zone = 80-100%, Yellow = 50-79%, Red = < 50%.
Frequently Asked Questions
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