Asthma Control Test (ACT) Calculator

Score asthma control using the five-item Asthma Control Test, a validated patient-reported measure of symptom burden over the previous four weeks.

🫁 Clinical Score📐 ACT = sum of 5 items, each scored 1–5 (range 5–25)🏥 Health
Asthma kept you from getting work or activities done
Shortness of breath
Woke at night or earlier than usual due to symptoms
Used rescue inhaler or nebuliser
How would you rate your asthma control
Please enter valid values.

Formula & Reference

VariableSymbolFormulaUnits
Asthma Control Test (ACT) Calculator—ACT = sum of 5 items, each scored 1–5 (range 5–25)points

Step-by-Step Examples

Example 1
Well Controlled

No activity limitation, no shortness of breath, no night waking, no rescue inhaler use, rates control as completely controlled.

  • All five items score 5
  • Total = 25
✓ ACT 25 — well controlled
Example 2
Not Well Controlled

Some activity limitation, breathless 3–6 times weekly, woke once a week, rescue inhaler 2–3 times weekly, somewhat controlled.

  • Work 3, breathlessness 3, night waking 3
  • Rescue use 3, self-rating 3
  • Total = 15
✓ ACT 15 — very poorly controlled
Example 3
Borderline

A little activity limitation, breathless once or twice weekly, no night waking, rescue inhaler once weekly, well controlled.

  • Work 4, breathlessness 4, night waking 5
  • Rescue use 4, self-rating 4
  • Total = 21
✓ ACT 21 — well controlled

Real-World Applications

📋
Routine Review
ACT provides a consistent numeric measure to compare across asthma appointments rather than relying on recall.
📈
Treatment Response
A change of three or more points is generally treated as clinically meaningful when assessing whether a treatment change worked.
🏠
Self-Monitoring
Patients can complete ACT at home, making it useful for tracking control between appointments.
📚
Guideline Integration
Symptom control assessment is a core component of asthma management frameworks alongside exacerbation risk and lung function.

Common Mistakes to Avoid

⚠️
Substituting ACT for lung function testing

ACT measures symptom burden only. Spirometry and peak flow assess airflow obstruction, and the two can diverge — some people perceive symptoms poorly.

⚠️
Overlooking rescue inhaler frequency

Frequent reliever use is one of the strongest signals of inadequate control and of exacerbation risk, even when other items look acceptable.

⚠️
Adjusting medication on the score alone

A low score should prompt review of inhaler technique, adherence, triggers, and comorbidities before treatment is escalated.

Frequently Asked Questions

What is the Asthma Control Test? ▾
A five-item patient-reported questionnaire covering activity limitation, breathlessness, night waking, rescue inhaler use, and self-rated control over the previous four weeks.
What ACT score means good control? ▾
20 or above generally indicates well-controlled asthma, 16–19 not well controlled, and 15 or below very poorly controlled.
How often should ACT be completed? ▾
Commonly at each asthma review, and more often during treatment changes or after an exacerbation.
Does ACT replace peak flow monitoring? ▾
No. It measures symptoms while peak flow and spirometry measure airflow. Both perspectives are useful, particularly since symptom perception varies between people.
Is there a version for children? ▾
Yes — the Childhood Asthma Control Test is validated for ages 4 to 11 and includes items completed by both child and caregiver.

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