PhenoAge Calculator: Your Blood-Based Biological Age (Free)
Updated 6/2/2026 · 3 min read
PhenoAge (Levine 2018) is one of the most cited blood-based aging clocks — it predicts mortality risk with an AUC around 0.88 from nine values you already get on a standard checkup.
Unlike epigenetic clocks that need a special DNA kit, PhenoAge uses routine labs, which makes it the most accessible validated option. Here's what it is and how to run it free.
The nine inputs
Albumin, creatinine, glucose, C-reactive protein (CRP), lymphocyte %, mean cell volume (MCV), red cell distribution width (RDW), alkaline phosphatase (ALP), and white blood cell count — plus your age. Most appear on an ordinary blood panel.
Don't have all nine? You can leave unknowns at typical values, or use the lifestyle survey instead.
What the number means
PhenoAge expresses your mortality risk as an equivalent age. A PhenoAge below your chronological age means lower-than-average risk for your years; above means higher. It's a research-grade estimate, not a clinical diagnosis.
Note: because it's centered on a reference cohort, average values can read a few years younger than your birthday — that's expected, not a bug.
Free and private
The calculator runs entirely on your device — your blood values are used for the math and never stored or transmitted. No account, no upload.
FAQ
What is PhenoAge?
A blood-based biological age model (Levine 2018) that converts nine standard lab values into an age reflecting mortality risk, validated at AUC ~0.88.
Is the PhenoAge calculator free?
Yes. It's free, requires no signup, and computes on your device — your blood values are never stored or sent to a server.
Is PhenoAge a medical diagnosis?
No. It's a research-validated estimate, not a clinical assessment. Discuss any abnormal values with a doctor.
DaysLeft is a statistical mirror, not a medical diagnosis. For health concerns, talk to a doctor. In crisis (US): call or text 988.