Biological age calculator (PhenoAge)
PhenoAge is a published estimate of biological age from nine routine blood results and your age. Type your results in the units on your report and it works out the estimate as a range, in your browser.
AI-verified against cited sources. Awaiting expert reviewLast reviewed 2026-10-03Aging & Longevity
Type your results above, or fill in the example, to see PhenoAge.
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Educational information, not medical advice. Blood Test Tracker doesn’t diagnose or treat, and it doesn’t replace your clinician. Talk with your clinician before changing medications, supplements or care.
How it’s worked out
The formula
PhenoAge (years) = 141.50 + ln[-0.00553 × ln(1 − M)] / 0.09165, where M = 1 − exp(−1.51714 × exp(xb) / 0.0076927) and xb = −19.907 − 0.0336 × albumin + 0.0095 × creatinine + 0.1953 × glucose + 0.0954 × ln(CRP) − 0.0120 × lymphocyte% + 0.0268 × MCV + 0.3306 × RDW + 0.00188 × ALP + 0.0554 × WBC + 0.0804 × age. Equation units: albumin g/L (= g/dL × 10), creatinine µmol/L (= mg/dL × 88.4), glucose mmol/L (= mg/dL ÷ 18.016), CRP mg/dL (= mg/L ÷ 10; natural log), lymphocytes % of white cells, MCV fL, RDW-CV %, ALP U/L, WBC 10^3 cells/µL, age in years at the blood draw. Algebraically equal to about 142.45 + 10.91 × xb.
When the equation works
Outside these limits the calculator says so instead of giving a number.
- Age: 20 years and over
- Not worked out when CRP is above 10 mg/L, a level that usually means a recent infection or injury.
- Not worked out when a result is outside the range of the survey the equation was built on.
Fasting before the blood test: recommended. No time of day is required. For comparisons over time, draw blood at a similar time of day and with the same fasting status each time.
A worked example
Example numbers, not anyone’s real results, run through the same code as the calculator above.
| Albumin | 4.5 g/dL |
|---|---|
| Creatinine | 0.9 mg/dL |
| Glucose | 90 mg/dL |
| CRP | 1 mg/L |
| Lymphocytes % | 30 % |
| MCV | 90 fL |
| RDW | 13 % |
| ALP | 70 U/L |
| WBC | 6 ×10³/µL |
| Age | 50 years |
| PhenoAge | 43 years, likely 38 to 48 |
What PhenoAge is
PhenoAge, also called Phenotypic Age, was published in 2018 by Levine and colleagues. It combines your age with nine routine blood results: albumin, creatinine, glucose, C-reactive protein (CRP), lymphocyte percent, mean cell volume (MCV), red cell distribution width (RDW), alkaline phosphatase (ALP) and white blood cell count. The equation was built to estimate the 10-year risk of dying in a large US health survey. That risk is then turned into an age: the age at which an average person in that survey had the same risk. Labs don't report PhenoAge. It is calculated from your results.
In US health-survey data, a person whose PhenoAge was one year higher than expected for their age had about 9% higher risk of dying during follow-up. People with more chronic conditions also tended to have a higher PhenoAge. These are patterns across large groups, not a forecast for one person. PhenoAge is a research tool. No guideline sets a normal range or a target for it, and it can't tell you why the number is what it is. Many people use it to follow a trend and to see which of their routine results are pulling the number up or down.
Read the full page on PhenoAge, with what a high or low result can mean.
Sources
The equation
- An epigenetic biomarker of aging for lifespan and healthspan, Aging (Albany NY) (2018)
- A new aging measure captures morbidity and mortality risk across diverse subpopulations from NHANES IV: A cohort study, PLOS Medicine (2018)
- Correction: A new aging measure captures morbidity and mortality risk across diverse subpopulations from NHANES IV: A cohort study, PLOS Medicine (2019)
- NHANES III Laboratory Procedures Manual (C-reactive protein in serum; hematology methods), CDC National Center for Health Statistics
- Genetic Variation Is Associated With C-Reactive Protein Levels in the Third National Health and Nutrition Examination Survey, Circulation (2006)
- Biomarkers of aging for the identification and evaluation of longevity interventions, Cell (2023)
AI-verified against cited sources. Awaiting expert review. Last reviewed 2026-10-03. The calculator is version 1.0.0 of our code for this equation, tested against published examples. How we build and check these pages.