Calculator · Biological Age

Biological Age Estimator

Enter four wearable-derived metrics to estimate your cardiovascular biological age range. Based on population norms from VO₂ max, RHR, sleep, and activity research.

Educational estimate only. Not a medical assessment. This tool applies published research correlations to produce a reference range. It does not diagnose any condition, replace clinical testing, or constitute medical advice. Epigenetic clocks and clinical biomarker panels provide more precise biological age estimates.
From your wearable's sleep report. 85%+ is optimal.
Use overnight RHR from your wearable.
Available on Garmin, Apple Watch, and Fitbit. Garmin is most validated.
Estimated Biological Age
Range: — to —
Metric contributions

How the estimate is calculated

This estimator applies age-adjustment factors derived from large-scale cardiovascular and longevity studies. Each metric contributes a delta (positive or negative years) relative to population medians for your age and sex. The contributions are weighted by research evidence quality.

MetricWeightPrimary research basis
VO₂ Max40%HUNT Fitness Study (Nes et al., 2013); Kodama et al. meta-analysis (2009)
Resting Heart Rate30%HUNT Study; Cooney et al. systematic review (2010)
Sleep Efficiency20%Buysse et al. (2008); Cappuccio et al. meta-analysis (2011)
Activity Level10%Wen et al. Lancet (2011); Lee et al. PLOS Medicine (2012)

What the research shows

VO₂ max is the single strongest predictor of all-cause mortality in published research — stronger than blood pressure, BMI, or cholesterol at most ages. A 1 MET improvement in cardiorespiratory fitness is associated with a roughly 15% reduction in cardiovascular mortality risk in multiple large cohort studies.

Resting heart rate carries independent predictive value: each 10 bpm increase above 60 bpm is associated with approximately 9–18 months of additional cardiovascular age in longitudinal data, depending on baseline fitness level.

Sleep efficiency below 75% is associated with accelerated inflammatory markers in multiple studies; the relationship between sleep quality and longevity is real but weaker than the VO₂ and RHR signals.

Limitations

This tool does not account for genetics, smoking status, nutrition, metabolic markers (HbA1c, lipids), blood pressure, or stress levels — all of which have documented effects on biological aging. Wearable-derived VO₂ max estimates carry ±3–5 ml/kg/min error margins versus laboratory measurement. Treat the output as a directional signal, not a precise number.

Clinical epigenetic clocks (Horvath, GrimAge, DunedinPACE) are the current scientific standard for biological age estimation. They use DNA methylation patterns from blood samples and carry much lower measurement error than this type of functional estimator.

Not a diagnostic tool. This biological age estimate is produced by applying population-level research correlations to your inputs. Individual variation is high. Do not use this output to make medical decisions, adjust medications, or replace clinical evaluation. If you have health concerns, consult a qualified healthcare provider.