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The Heaviness of Smoking Index (HSI) is a standard, published 2-item shortened version of the Fagerstrom Test for Nicotine Dependence, using just time to first cigarette and cigarettes per day, each scored 0-3, for a total 0-6 score. This calculator is for general reference and educational purposes only — it is not a medical diagnosis. Consult a doctor or qualified professional for actual nicotine dependence assessment.
How it works
Answer the 2 standard HSI questions using the dropdown options. The tool sums the published point values and classifies the total against commonly cited dependence bands.
- Enter how soon after waking do you smoke your first cigarette?.
- Enter how many cigarettes per day do you smoke?.
- Click Calculate to see your results.
Examples
Smoking within 5 minutes of waking, 25 cigarettes per day
3 (time to first cigarette) + 2 (cigarettes per day) = 5 — high dependence.
Who should use it
- A quick nicotine dependence check before a quit attempt.
- Smoking cessation research and clinical practice.
Industry applications
- Smoking cessation programs
- Addiction medicine research
Advantages
- Very quick — just 2 questions — while retaining much of the FTND's predictive value.
- Widely used in smoking cessation research as a rapid screen.
Limitations
- Less detailed than the full 6-item FTND.
- Self-reported answers may not perfectly reflect actual smoking behavior.
Common mistakes to avoid
- Underestimating cigarettes per day by not counting all cigarettes smoked in a typical day.
- Treating the score as a fixed label rather than one input to a quit-planning conversation with a doctor.
Best practices
- Answer based on your typical, current smoking pattern for the most meaningful score.
Tips
- Discuss your HSI score with a doctor when planning a quit attempt.