Cigarettes per day (cigarettes/day) Enter how many cigarettes you smoke daily (e.g., 15)

Years smoked (years) Enter the total number of years you have smoked (e.g., 10.5)

Quick Examples:

Moderate Smoker (20yrs) Light Smoker (10yrs)

Calculate Clear

This calculator is a screening tool only, not a diagnostic instrument. It is not intended to replace professional medical evaluation. Consult a healthcare provider.

What Is Pack-Years

Pack-years is a way to measure how much a person has smoked in their life. It looks at how many packs of cigarettes someone smokes each day and for how many years they have done it. This number helps doctors understand the total amount of smoke exposure a person has had. It is often used to check the risk for lung problems.

How Pack-Years Is Calculated

Formula

To find the pack-years, you first divide the number of cigarettes you smoke each day by 20. This is because there are usually 20 cigarettes in one pack. This tells you how many packs you smoke per day. Then, you multiply that number by the total years you have been smoking. The final answer is your total pack-years.

Why Pack-Years Matters

Knowing your pack-years number helps you understand your smoking history. It is often used by doctors to screen for lung health risks.

Why Smoking History Is Important for Lung Health

Smoking for a long time can hurt your lungs. A high number of pack-years may mean there is a higher statistical association with lung disease. This calculation helps doctors decide if you need special tests to check your lungs.

Pack-Years vs. Total Cigarettes

Total cigarettes count every single cigarette smoked. Pack-years looks at the rate of smoking over time. Doctors use pack-years more often because it shows both how much and how long someone has smoked. This gives a better picture of risk than just counting cigarettes.