VO2 Max Calculator

This method uses your resting heart rate as a proxy for aerobic fitness — a lower resting heart rate relative to your estimated max generally indicates a more efficient cardiovascular system. We calculate your estimated max heart rate using the Tanaka formula (HRmax = 208 − 0.7 × age), then apply the Uth-Sørensen-Overgaard-Pedersen formula: VO2max = 15.3 × (HRmax ÷ resting HR).

This is the least accurate of the three methods here. Resting heart rate swings with caffeine, stress, hydration, sleep quality, and even time of day, so a single reading can shift your result meaningfully. For the most consistent number, measure your resting heart rate first thing in the morning, lying down, before caffeine or any activity. If you're willing to do a short physical test instead, the Cooper Run Test or Rockport Walk Test tabs above are both more accurate.

Source: Uth, N., Sørensen, H., Overgaard, K., & Pedersen, P.K. (2004). Estimation of V̇O2max from the ratio between HRmax and HRrest — the Heart Rate Ratio Method. European Journal of Applied Physiology, 91(1), 111–115.

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The Cooper test estimates VO2max from how far you can run in 12 minutes at maximal, sustained effort: VO2max = (distance in meters − 504.9) ÷ 44.73. It was developed by Dr. Kenneth Cooper for the U.S. Air Force as a fast field test that didn't require a lab.

This test requires genuine maximal effort for the full 12 minutes, so it's best suited to people who are already comfortable running hard and have appropriate fitness/health clearance to do so — it's not a casual jog.

Source: Cooper, K.H. (1968). A means of assessing maximal oxygen intake. JAMA, 203(3), 201–204.

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The Rockport Walk Test estimates VO2max from your time to walk one mile as fast as possible (without running) and your heart rate immediately at the finish, combined with your age, sex, and weight: VO2max = 132.853 − (0.0769 × weight in lb) − (0.3877 × age) + (6.315 × sex, male=1/female=0) − (3.2649 × walk time in minutes) − (0.1565 × ending heart rate).

In its original validation, this test correlated at r=0.88 with lab-measured VO2max — making it one of the better field-test options, especially for people who prefer walking over running or who can't run safely.

Source: Kline, G.M., et al. (1987). Estimation of VO2max from a one-mile track walk, gender, age, and body weight. Medicine & Science in Sports & Exercise, 19(3), 253–259.

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Whichever method you use above, your result is classified against the same age- and sex-normed reference data, since all three produce the same ml/kg/min unit. The categories — Poor, Fair, Average, Good, Excellent, Superior — aren't fixed numbers; they're percentile bands within your own age-and-sex bracket (below the 20th percentile = Poor, 20th–39th = Fair, 40th–59th = Average, 60th–79th = Good, 80th–94th = Excellent, 95th and above = Superior). That means "Good" means a different raw number for a 25-year-old woman than for a 55-year-old man.

The reference table only publishes values at the 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles for each bracket, so where your result falls between two published points, we linearly interpolate to place it — a standard, transparent approximation, not a guess.

These are general population norms from a large reference dataset, not a personal verdict — individual context like training history and health conditions affects where any one person "should" fall, the same way BMI can't tell fat from muscle. Treat your category as a reference point for tracking change over time, not a grade.

Source: American College of Sports Medicine. ACSM's Guidelines for Exercise Testing and Prescription (11th ed.). Table 4.7: normative values for VO2max by age and sex, based on Cooper Institute / FRIEND registry data.