HSI Calculator (Heaviness of Smoking Index)
HealthCalculate the Heaviness of Smoking Index (HSI) from time to first cigarette and cigarettes per day. A quick, validated 2-question nicotine dependence screen.
Reviewed by the thecalcu.com team · Last updated July 23, 2026
HSI Total Score
What is a HSI Score?
The HSI Calculator scores the 2-question Heaviness of Smoking Index, a fast screening proxy for nicotine dependence combining time to first cigarette and cigarettes smoked per day. It's a shorter alternative to the full Fagerstrom Test for Nicotine Dependence.
This is a screening tool, not a diagnosis.
Why Use an HSI Calculator?
HSI captures much of the signal from the longer Fagerstrom Test using just two quick questions, making it convenient for a fast self-check. This calculator scores it instantly and privately, entirely in your browser.
Who Should Use This Calculator?
- Smokers wanting a very quick dependence self-check without the full 6-question Fagerstrom Test.
- Students of public health learning about abbreviated screening tool design.
- Healthcare educators demonstrating how HSI relates to the full Fagerstrom Test.
- Anyone curious about their nicotine dependence level.
What Insights Does the HSI Calculator Give You?
The HSI Total Score (0-6) is the sole output, reflecting your combined answers on time to first cigarette and cigarettes per day. Higher totals generally indicate stronger physical dependence; this calculator does not provide a clinical interpretation.
How to use this HSI Score calculator
- Answer how soon after waking you smoke your first cigarette.
- Answer how many cigarettes per day you smoke.
- Read your HSI Total Score instantly.
Show formula & methodology ↓Show less ↑
Formula & Methodology
Both questions are scored 0-3. Total Score = Time to First Cigarette Score + Cigarettes per Day Score (range: 0-6) Worked example, smoking within 5 minutes of waking (3) and smoking 25 cigarettes per day (2): Total Score = 3 + 2 = 5
Frequently Asked Questions