Pack-Year Calculator
Calculate your cumulative smoking exposure. A crucial clinical metric used to determine lung cancer screening eligibility and assess pulmonary risk.
Last updated: March 3, 2026
Clinical Screening Alert
If this calculator returns a score of 20 pack-years or higher, and you are between 50-80 years old, ask your doctor about an LDCT lung cancer screening. It could save your life.
Note: 1 standard commercial pack contains 20 cigarettes.
Total duration of smoking the declared amount daily.
10
Your cumulative exposure represents a moderate to high risk for COPD, cardiovascular disease, and lung cancer. Quitting is highly recommended.
This tool is for informational risk assessment and cannot diagnose lung cancer or COPD. Please consult a healthcare professional regarding cancer screening and smoking cessation.
Understanding The 20 Pack-Year Rule
In 2021, the USPSTF expanded the eligibility for life-saving lung cancer screenings, lowering the threshold from 30 pack-years down to 20 pack-years. Here is who should be screened:
Age 50 to 80
You fall within the age bracket where lung cancer incidence begins to peak, making routine screening highly beneficial.
20+ Pack-Years
You have accumulated a smoking history equal to smoking a pack a day for 20 years (or half a pack for 40 years).
Smoking Status
You are either a current smoker, or you have quit smoking relatively recently (specifically, within the last 15 years).
Why is LDCT so important? Low-Dose Computed Tomography (LDCT) can spot tiny lung tumors years before they cause symptoms like coughing or shortness of breath. Catching lung cancer in Stage 1 dramatically increases the survival rate.
Frequently Asked Questions
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A quick way for clinical staff to check screening eligibility criteria.
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