Most “biological age” calculators are lifestyle quizzes dressed up as science — answer a few feel-good questions, get a number that flatters you. This one is different. It runs the actual published PhenoAge algorithm on your real blood markers, and it's honest about what it can and can't see.
The first number I wanted out of all this research was an honest one about myself — so I built this to run the real published formula on your bloodwork, not a feel-good quiz. At 60, I'd rather know than be flattered.
In 2018, Morgan Levine and colleagues published PhenoAge — a formula that takes nine ordinary blood markers, plus your age, and produces a single number: the age your body is actually behaving like. It was validated against real mortality and disease data from tens of thousands of people. It predicts who gets sick and who doesn't better than the calendar does.
That's the difference between this and the quizzes. A quiz asks if you exercise and eat your vegetables, then rewards your good intentions. PhenoAge ignores your intentions and reads what's measurably happening in your blood. You need a recent lab panel to use it — and that requirement is exactly why it means something.
Enter the values from a recent blood test (US lab units). All nine markers plus your age are required. Nothing is sent anywhere — the math runs entirely in your browser.
Don't have these numbers yet? You only need three common tests: a Comprehensive Metabolic Panel (CMP), a Complete Blood Count with differential (CBC w/ diff), and an hs-CRP. Your doctor can order all three, or you can order them yourself online for roughly $40–80 total in most areas. Bookmark this page and come back when you have the results in hand.
This is where we part ways with the hype. PhenoAge is genuinely useful, but it is not magic, and anyone who sells it as a precise verdict is overselling it.
Don't panic, and don't reach for the supplement aisle. The markers PhenoAge reads — inflammation, blood sugar, kidney and liver signals, immune balance — respond most reliably to the boring, proven things: real cardio and strength training, sleep, body composition, and getting an actual medical workup if something looks off. The trendy longevity pills mostly don't move these numbers, no matter what the ad says.
The interventions that actually move these markers — in the order worth doing them — are laid out in our anti-aging guide, with the evidence behind each one and zero supplement hype.
See What Actually WorksIt's an estimate of how old your body is functioning, based on measurable markers rather than your birth date. Two 60-year-olds can have biological ages a decade apart.
A CMP (albumin, creatinine, glucose, alkaline phosphatase), a CBC with differential (lymphocyte %, MCV, RDW, WBC), and hs-CRP. All common and inexpensive.
Yes — it's a peer-reviewed algorithm (Levine et al., 2018) that predicts mortality and disease risk better than chronological age. It is still a single snapshot, so treat it as a directional signal you can act on and re-measure, not a final verdict.
— Scott Covert, 60, skeptic, not a physician. I built this for my own body first. Got a claim you want run through the BS Detector, or think I got something wrong? Tell me and I'll dig in.