Fitness Age Estimate Calculator
Estimate your "fitness age" from your VO2max relative to what is typical for your chronological age.
How it works
Fitness age = (VO2max intercept − VO2max) ÷ decline per year · lower fitness age = better than typical for your years
Fitness age converts your VO2max into the chronological age at which that value would be typical. Because aerobic capacity falls at a fairly steady rate over adulthood, a high VO2max maps onto a younger equivalent age, and a low one onto an older age. It is a motivational, population-level estimate — not a clinical measure of biological aging.
Worked example
For a man, typical VO2max ≈ 57 − 0.40 × age. A VO2max of 45 solves to (57 − 45) ÷ 0.40 = 30, so a 35-year-old with that value has a fitness age of about 30 — five years younger than his actual age.
Frequently asked questions
What is fitness age?
It is the age at which your current aerobic fitness would be average. If your VO2max matches that of a typical 30-year-old, your fitness age is 30 regardless of your birthday.
Is fitness age the same as biological age?
No. Biological age draws on many markers — blood pressure, blood glucose, cell aging and more. Fitness age reflects only cardiorespiratory fitness, though that is one of the strongest single predictors of longevity.
How do I lower my fitness age?
Raise your VO2max through regular aerobic training, particularly higher-intensity intervals, plus consistent moderate activity. Improvements of a few years are realistic over several months of training.
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Educational estimate only, not medical advice. Individual physiology varies — consult a qualified professional before changing your training or health routine.