Biological Age Calculator

PhenoAge is among the most accurate biological age estimators that uses only standard blood tests. In the original Levine 2018 study, it outperformed chronological age for predicting all-cause mortality, cardiovascular events, cancer incidence, and physical function decline across more than 11,000 adults in NHANES III with up to 25 years of follow-up. Each year of “age acceleration” (PhenoAge above chronological age) was associated with roughly 9% higher all-cause mortality risk. More expensive aging clocks based on DNA methylation (Horvath, GrimAge) are somewhat more precise, but they require specialized testing. PhenoAge runs on a standard blood panel.

The PhenoAge formula was derived from a population dataset that included both sexes, and testosterone wasn’t among the variables that survived the statistical selection process for the most predictive composite score. That doesn’t mean testosterone is unimportant — it absolutely affects long-term health — it just wasn’t one of the nine markers needed for the most accurate composite. Testosterone influences several of the markers that are in PhenoAge (CRP, glucose, body composition effects on ALP and WBC), so its effects show up indirectly. A complete workup should include testosterone alongside the PhenoAge markers, which is why the ApexBlood panel covers both — all nine PhenoAge inputs plus total testosterone and free testosterone in a single draw.

Measurably within 6 to 12 months, sometimes faster. Inflammation (CRP) responds within weeks to changes in diet, sleep, and body composition. Glucose responds within 1 to 3 months. Red blood cell parameters (MCV, RDW) shift over 3 to 6 months as new cells replace older ones. Liver and kidney markers respond over 3 to 12 months. Several clinical studies have documented biological age reductions of 2 to 5 years over a 12-month period in adults who systematically addressed sleep, body composition, inflammation, and metabolic markers. The longer the intervention is sustained, the more durable the change.

Mathematically, the highest-weighted variable in the PhenoAge formula is RDW (red cell distribution width), followed by glucose, MCV, and CRP. Practically, the markers most worth addressing in mid-life are the ones reflecting modifiable systems: CRP (inflammation, responsive to lifestyle), glucose (metabolic health, highly modifiable), and ALP (which reflects liver health and is affected by body composition and alcohol). RDW and MCV are harder to move but worth tracking — when they shift, something meaningful is changing.

No. The PhenoAge research shows associations, not destinies. People with elevated biological age have higher statistical risk, but the relationship is highly modifiable — multiple intervention studies have shown that meaningful improvement over 6 to 12 months is achievable for most adults. The number is most useful as a starting point and a tracking tool, not a verdict. If your number is concerning, the productive response is to get a complete workup, identify which specific markers are driving the gap, and address them. The same biology that produced the elevated number is the biology that responds to intervention.

PhenoAge was validated in a general population and assumes no acute illness at the time of testing. If you have an active infection, recent surgery, or an inflammatory condition that’s actively flaring, your CRP and WBC values will be elevated for reasons unrelated to long-term biological aging — and the calculator will overestimate your bio age. For known chronic conditions (well-controlled hypertension, treated thyroid disease), the calculator still produces useful estimates but the result should be interpreted with a clinician. The number is most useful when you’re at baseline health, not when something acute is happening.

No. Your inputs exist only in your browser session. Nothing is stored, logged, or attached to any account. You can run the calculator as many times as you want without anything being saved on our end.