Asthma Action Plan Calculator

Zone-based action plan from peak flow and symptoms.

Personal Best PEF (L/min)

Current PEF (L/min)

Daytime Symptom Days/Week

Night Awakenings/Week

Rescue Inhaler Days/Week

Activity Limitation (0-5)

Tab to move between fields

Current Zone (0=Green, 1=Yellow, 2=Red)

% of Personal Best84%

Green Zone Min PEF (L/min)400

Yellow Zone Min PEF (L/min)250

Control Score (5-25)21

Control Level (0=Well, 1=Not Well, 2=Poor)0

Recommended NAEPP Step (1-6)1

How to Use This Calculator

Enter your personal best PEF (L/min) established during a well period.
Enter today's current PEF (L/min) and rate daytime symptom days/week, night awakenings/week, and rescue inhaler days/week.
The calculator determines your zone: Green (>=80% personal best), Yellow (50-79%), or Red (<50%).
Review zone-specific action steps and medication guidance based on your current zone.
Track daily PEF readings over time to identify worsening trends before a full exacerbation.

How the result changes with Personal Best PEF (L/min)

Personal Best PEF (L/min)	Current Zone (0=Green, 1=Yellow, 2=Red)
180	0
380	0
620	1
820	1

Personal Best PEF (L/min): Highest peak flow achieved when asthma is well controlled.
Current PEF (L/min): Today's measured peak expiratory flow.
Daytime Symptom Days/Week: Number of days per week with daytime asthma symptoms.
Night Awakenings/Week: Number of nights per week woken by asthma symptoms.
Rescue Inhaler Days/Week: Days per week rescue inhaler is needed (not counting pre-exercise use).
Activity Limitation (0-5): 0 = No limitation, 5 = Severe limitation of daily activities.

Current Zone (0=Green, 1=Yellow, 2=Red): 0 = Green (well controlled), 1 = Yellow (caution), 2 = Red (medical alert).
% of Personal Best: Current PEF as percentage of personal best.
Green Zone Min PEF (L/min): PEF values ≥ this level (80% personal best) = green zone.
Yellow Zone Min PEF (L/min): PEF values ≥ this level (50% personal best) but below green = yellow zone.
Control Score (5-25): Composite asthma control score. ≥20 = well controlled, 16-19 = not well, ≤15 = very poor.
Control Level (0=Well, 1=Not Well, 2=Poor): 0 = Well controlled, 1 = Not well controlled, 2 = Very poorly controlled.
Recommended NAEPP Step (1-6): Suggested NAEPP therapy step. Higher = more intensive treatment.

Identify Input Parameters
4 parameters
Personal Best PEF (L/min) = 500, Current PEF (L/min) = 420, Daytime Symptom Days/Week = 2, Night Awakenings/Week = 1 = 6 input(s) provided
Calculate Current Zone
0 = 0
Calculate % of Personal Best
% of Personal Best = (currentPEF / personalBest) * 100
84 = 84
Calculate Green Zone Min PEF
Green Zone Min PEF = round(personalBest * 0.80)
400 = 400