# Chronological age

Chronological age is simply the time since you were born, usually counted in years. It is the standard reference in demography, medicine, and epidemiology, and it is still one of the strongest single predictors of death and many age-related conditions. But unlike biological age, it does not capture how fast any one person is declining. Two people the same chronological age can differ a lot in fitness, disease risk, and remaining healthspan. And depending on the group and the outcome, other measures can match or beat its predictive power.

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_Canonical: https://longevity-switzerland.com/en/glossary/chronological-age · Part of Longevity Cities · Updated 2026-06-22_