Biological Age
Calculator
Chronological age counts the years. Phenotypic age asks how old your physiology looks. Enter nine values from a standard blood panel to estimate your PhenoAge using the peer-reviewed Levine algorithm.
Your panel
Estimated phenotypic age
How this works
Methodology reviewed July 2026Chronological age counts the years; phenotypic age asks how old your physiology reads. This tool implements the published Levine PhenoAge algorithm (Levine et al., Aging, 2018), a Gompertz-based mortality model built from nine routine blood biomarkers plus your calendar age. Your US-conventional lab values are converted internally to the formula's SI units, combined into a linear predictor, run through the model's mortality-score and survival transforms, and mapped back to a single number in years — your estimated phenotypic age. It correlates with mortality and healthspan at the population level, but one reading is a snapshot, not a verdict.
PhenoAge is the peer-reviewed Levine et al. (2018) algorithm — not a single
closed-form equation but a multi-step model:
1. Nine biomarkers + chronological age enter a weighted linear predictor:
albumin (g/L), creatinine (µmol/L), fasting glucose (mmol/L), ln(CRP mg/dL),
lymphocyte %, mean cell volume (fL), red-cell distribution width %,
alkaline phosphatase (U/L), white-blood-cell count (10³/µL), age (yrs).
2. That predictor feeds a Gompertz mortality-risk term over a 120-month horizon,
giving a 10-year mortality score M.
3. M is inverted through the model's calibration transform to return
phenotypic age in years.
US-conventional inputs are converted first (e.g. albumin g/dL ×10 → g/L;
creatinine mg/dL ×88.42 → µmol/L; glucose mg/dL ÷18.0182 → mmol/L).
Chronological age · Albumin · Creatinine · Fasting glucose · C-reactive protein (hs-CRP) · Lymphocyte % · Mean cell volume · Red-cell distribution width · Alkaline phosphatase · White blood cell count
Estimated phenotypic age (years) · Difference vs chronological age · Interpretation
- All nine biomarkers come from a standard blood panel drawn under normal (typically fasting) conditions.
- Values are entered in the labelled US-conventional units; the tool converts them to the SI units the formula expects.
- You are a generally healthy adult without an acute illness or infection that would transiently distort inflammatory and cell-count markers.
- PhenoAge is a population-level research measure, not a diagnosis or a clinical age.
- It was derived largely in a US (NHANES) cohort and may transfer imperfectly to other populations.
- Several inputs (CRP, WBC, glucose) swing with acute illness, so a single reading can mislead — trends matter far more.
- A value near your chronological age is well within normal noise; small differences should not be over-read.
- This is an educational estimate, not a diagnosis or a mortality prediction for you as an individual.
- Do not change medication, supplements, or lifestyle on the strength of one number — discuss results, especially an "older" reading, with a clinician.
References
This calculator is for educational purposes only and is not medical advice, diagnosis, or treatment. Results are estimates based on published formulas and population averages — your individual values may differ. Nothing here is calculated on a server: everything runs in your browser and no data is stored or sent anywhere. Always consult a qualified clinician before making health, medication, or training decisions.