Your chronological age tells you how many years you've lived. Your biological age tells you how fast you're living them. Answer 8 evidence-based domains and get your personalized assessment in under 4 minutes.
Have recent blood work? Calculate your PhenoAge from nine lab values →
A lifestyle-based estimate. The domain weights draw on research on fitness, metabolic health, sleep, strength, stress and social connection (sources below). It does not use the PhenoAge formula, which needs nine blood tests, and it has not been validated against measured biological age.
Your chronological age and sex are the baseline against which your biological age is calculated. These are fixed inputs — everything else you can change.
Used as the baseline. Your biological age will be calculated relative to this number — younger means you're aging slower than your peers, older means faster.
Years old (must be 18–100)
Sex affects reference ranges for nearly every longevity biomarker — from optimal VO₂max to cardiovascular risk thresholds. We use it only for scoring accuracy.
VO₂max — your maximal oxygen uptake — is the single most powerful predictor of longevity in the scientific literature, surpassing smoking status, diabetes, and hypertension in predictive value.
Be honest — this is the highest-impact domain in the assessment.
A lower resting heart rate reflects greater cardiovascular efficiency. Elite endurance athletes often sit at 40–50 bpm; optimal longevity range is below 60 bpm.
Only 6.8% of US adults had optimal cardiometabolic health across five measures in a 2022 analysis of national survey data. Metabolic dysfunction is the upstream driver of cardiovascular disease, dementia, and accelerated aging.
Diet is the primary driver of metabolic health. We use this as a proxy for fasting glucose, insulin sensitivity, and inflammatory load.
These conditions directly indicate metabolic dysfunction and accelerate biological aging through glycation, inflammation, and mitochondrial impairment.
Sleep is not optional recovery — it is the primary mechanism by which the glymphatic system clears amyloid-β from the brain, growth hormone is secreted for tissue repair, and immune memory is consolidated.
Duration alone isn't enough — architecture matters. Disrupted sleep fails to deliver the deep slow-wave sleep needed for cellular repair and the REM sleep required for cognitive consolidation.
Visceral fat — not total body weight — is the metabolically active tissue that drives inflammation, insulin resistance, and accelerated aging. Meanwhile, muscle mass is increasingly recognized as the primary organ of longevity.
This is about fat distribution and muscle quality, not just weight. A person can have a "normal" BMI but high visceral fat — what's called "TOFI" (Thin Outside, Fat Inside).
Resistance training is the main proven way to rebuild muscle lost with age, and muscle-strengthening activity is associated with 10–17% lower all-cause mortality.
Chronic psychological stress is not merely uncomfortable — it measurably accelerates epigenetic aging by activating the HPA axis, shortening telomeres, driving chronic inflammation, and impairing immune function.
Mindfulness-Based Stress Reduction (MBSR) has the strongest RCT evidence — 8-week programs reduce perceived stress and anxiety; effects on biological aging markers are uncertain.
Smoking, alcohol, and social connection are among the most powerful lifestyle determinants of biological age. The effect sizes are large enough to meaningfully shift results in either direction.
Smoking is among the highest-impact modifiable risk factors for early death. Even 5–10 cigarettes/day produces meaningful harm.
No amount of alcohol is considered safe for cancer risk. US guidelines advise no more than one drink a day for women and two for men, and less is better. Heavy drinking accelerates brain aging and liver disease.
The science of longevity's most underrated domain. In a 2015 meta-analysis, social isolation was associated with 29% higher odds of death. Purpose and meaning in life predict slower biological aging independent of all other factors.
Quality matters more than quantity. One or two deep relationships are more protective than dozens of superficial ones. Loneliness is not about being alone — it's about feeling disconnected.
In a 2019 study of 6,985 US adults over 50, those with the weakest sense of purpose had 2.43 times the risk of death of those with the strongest over about four years.
Scoring your answers across 8 research-informed domains.
Your estimated biological age
Medical Disclaimer: This calculator provides an educational estimate based on self-reported lifestyle factors and population-level research. It is not a medical diagnosis and cannot replace clinical biomarker testing (bloodwork, VO₂max testing, DEXA scan, epigenetic clocks such as TruMe, or glycan-based tests such as GlycanAge). For precision biological age testing, consult your physician or request the Levine PhenoAge panel, which uses actual biomarkers. Results reflect general trends in population research, not your individual physiology.
The questionnaire above is a lifestyle estimate. If you have recent blood work, this calculator applies the published Phenotypic Age model (Levine et al., 2018): nine routine lab values plus your age, weighted by how strongly each predicted 10-year mortality in a large US national survey, then expressed in years (sources 3 and 16 below).
Use values from the same blood draw, ideally when you are well: an infection raises CRP and white cells. Units are US conventional; the calculator converts them to the units in the paper (albumin g/L, creatinine µmol/L, glucose mmol/L, CRP mg/dL). The model was built in adults 20 and over. It estimates risk at the population level and is not a diagnosis.
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The page has two parts. The lifestyle questionnaire scores habits across several domains and is an educational estimate, not a validated clock. The PhenoAge calculator uses nine routine blood markers plus your age in the formula published by Levine and colleagues, who built PhenoAge from composite clinical measures of phenotypic age (Levine 2018).
Neither part is a diagnosis. PhenoAge depends on accurate lab values in the right units; one abnormal result, such as during an infection, can shift it. Lowering your score has not been shown to change health outcomes.
A PhenoAge below your actual age suggests your blood markers look like those of a younger person, and above suggests older. Use it to track trends over time with the same laboratory, and focus on the specific markers that pull the score up.
This tool uses a weighted scoring model across 8 research-informed domains. Each domain is grounded in peer-reviewed research, with weights assigned proportional to effect size in mortality and aging studies. Here's exactly what we measure and why.
Explore 120 long-form articles on every longevity domain, or build your personalized protocol.