PhenoAge and the Klemera–Doubal Method (KDM) are both peer-reviewed ways to estimate biological age from blood markers — but they answer related, distinct questions. PhenoAge is tuned to mortality risk; KDM is tuned to the aging trajectory of a reference population.
What this guide will cover
- The idea behind each method
- Mortality risk (PhenoAge) vs. aging trajectory (KDM)
- Why the two numbers can differ for the same person
- When each is the more useful lens
This guide is being expanded. In the meantime, try both: the PhenoAge calculator and the KDM calculator.
Educational only — not medical advice. Always consult a qualified healthcare professional about your results.