Pack-Years Calculator
Smoking history and lung cancer screening eligibility.
Your result
US guidelines suggest yearly low-dose CT for adults aged 50–80 with at least 20 pack-years who smoke now or quit within 15 years. Ask your clinician.
Medical disclaimer: This tool is for education and is not medical advice. Read more.
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Frequently asked questions
What does the Pack-Years Calculator do?
Smoking history and lung cancer screening eligibility. Enter your values and the result and chart update instantly.
How accurate is it?
It uses published, widely used formulas. Results are estimates for education and planning, not a diagnosis. Talk to a qualified clinician about decisions affecting your health.
Is my information stored or shared?
No. All calculations run in your browser and nothing you type is sent to a server or saved.
What can I search to find this tool?
People find it by searching for: do i qualify for lung screening; smoking history calculator; lung cancer risk.