Heaviness of Smoking Index Calculator

What Is the Heaviness of Smoking Index?

The Heaviness of Smoking Index (HSI) is a two-question measure of nicotine dependence drawn from the Fagerstrom Test for Nicotine Dependence. It asks how soon you smoke your first cigarette after waking and how many cigarettes you smoke per day. HSI is widely used in research and smoking-cessation planning because it is quick yet predictive. For the full six-item assessment, use the Fagerstrom Test for Nicotine Dependence Calculator.

How the HSI Score Works

Time to first cigarette scores 0 to 3 points: within 5 minutes earns 3, 6 to 30 minutes earns 2, 31 to 60 minutes earns 1, and after 60 minutes earns 0. Daily cigarette count scores 0 to 3: 10 or fewer earns 0, 11 to 20 earns 1, 21 to 30 earns 2, and 31 or more earns 3. The total HSI ranges from 0 to 6.

Score Interpretation

Scores of 0 to 2 suggest low nicotine dependence. Scores of 3 to 4 suggest moderate dependence and may benefit from structured quit support or nicotine replacement. Scores of 5 to 6 suggest high dependence and often warrant stronger pharmacotherapy and counseling. HSI helps clinicians tailor cessation strategies but does not replace medical advice.