Calculator · Respiratory

Smoking pack-years

Cumulative tobacco exposure.

What it is for

COPD / lung-cancer risk, targeted CT screening eligibility, documentation.

Use the working calculator

The working Smoking pack-years calculator is on our calculators page. It is free and needs no account. Enter the values and it shows the result with the reading that goes with it.

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What you enter

The calculator asks for 2 items.

  • Cigarettes per day (/day)
  • Years smoked (yrs)

How the result is read

The result is shown as Pack-years in pack-yrs. Formula: (cigarettes per day ÷ 20) × years smoked.

The calculator reports one of these readings, with the action that goes with it: Lower cumulative exposure; Significant exposure; Heavy exposure.

Sources

These are the sources the calculator cites. Check the current version before relying on a threshold.

Related

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For qualified clinicians. A score supports a clinical decision and does not make it: check the inputs, read the cited source, and use the tools in your clinical system for patient care where one is provided.