VO2 Max Calculator

VO2 max is the most oxygen your body can use during hard exercise, and a strong marker of aerobic fitness. Estimate yours with one of three field tests and compare it with lab-measured values for people your age.

Your details

Run as far as you can in 12 minutes on a flat course.
years
Sex
km

Use an existing result if you have one. If you have symptoms such as chest discomfort or unusual shortness of breath, or you have a known heart, metabolic or kidney condition, check the ACSM screening guidance before attempting a timed test.

Your results

Pick a test and enter your results to estimate your VO2 max.

How to use it

  1. Choose a 12-minute run, a timed mile walk or the heart-rate ratio. The ratio uses existing measurements and needs no exercise.
  2. Enter your test results, age and sex. Check the screening guidance before attempting a timed effort.
  3. Read your estimated VO2 max and, where available, compare it with lab values for your age and sex.

How it's calculated

Cooper 12-minute run. Run as far as you can in 12 minutes on a flat course. Cooper (1968) found distance and treadmill-measured VO2 max were closely related:

VO2 max = (metres covered − 504.9) ÷ 44.73

Example: 2,600 m gives (2,600 − 504.9) ÷ 44.73 = 46.8 mL/kg/min.

Rockport 1-mile walk. For this field version, walk one measured mile briskly without running and record your pulse right at the finish. The calculator accepts walk times from 10 to 30 minutes. Kline et al. (1987) studied 343 adults aged 30 to 69 and measured heart rate during the final quarter of the walk:

VO2 max = 132.853 − 0.0769 × weight (lb) − 0.3877 × age + 6.315 (men only) − 3.2649 × time (min) − 0.1565 × heart rate

Heart rate ratio. No exercise needed. Uth et al. (2004):

VO2 max = 15.3 × max heart rate ÷ resting heart rate

If you don’t enter a measured max, the calculator estimates it with Tanaka’s formula, 208 − 0.7 × age. The 15.3 factor came from well-trained men, so the estimate may be less accurate in other groups.

Comparison. Eligible run and walk estimates are compared with the FRIEND registry: VO2 max measured by gas analysis during treadmill tests in apparently healthy US adults (Kaminsky et al. 2015). The table shows the 5th to 95th percentiles for your age and sex; the calculator shows where the estimate falls among those lab values. It skips the comparison for the heart-rate ratio and for Rockport estimates outside the study age range.

Limits. Field tests estimate; only a lab test with gas analysis measures VO2 max. Field results can differ from a lab result. Before doing a timed effort, follow the screening guidance above.

Sources

  1. Cooper, K. H. (1968). A means of assessing maximal oxygen intake. Correlation between field and treadmill testing. JAMA, 203(3), 201–204.
  2. Kline, G. M., Porcari, J. P., Hintermeister, R., 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.
  3. Uth, N., Sørensen, H., Overgaard, K., & Pedersen, P. K. (2004). Estimation of VO2max from the ratio between HRmax and HRrest, the heart rate ratio method. European Journal of Applied Physiology, 91(1), 111–115.
  4. Kaminsky, L. A., Arena, R., & Myers, J. (2015). Reference standards for cardiorespiratory fitness measured with cardiopulmonary exercise testing: data from the Fitness Registry and the Importance of Exercise National Database. Mayo Clinic Proceedings, 90(11), 1515–1523.
  5. Tanaka, H., Monahan, K. D., & Seals, D. R. (2001). Age-predicted maximal heart rate revisited. Journal of the American College of Cardiology, 37(1), 153–156.
  6. American College of Sports Medicine. Exercise preparticipation screening guidelines.

Questions

What is a good VO2 max?

It depends on age and sex. In the FRIEND data, the middle value (50th percentile) is 42.4 mL/kg/min for men in their 30s and 30.2 for women in their 30s. Above the 75th percentile is well above average for your group.

Which test is most accurate?

Accuracy depends on how closely you follow the test protocol and how well the study population matches you. Cooper studied male Air Force personnel. Rockport studied adults aged 30 to 69, and the heart-rate ratio was fitted in well-trained men.

Why is my watch's VO2 max different?

Watches estimate VO2 max from your pace and heart rate during runs, with their own formulas. Different methods give different numbers. Compare each method with itself over time rather than with each other.

Can I improve my VO2 max?

Yes. Regular endurance training raises it, especially with some hard intervals on top of easy aerobic work. Gains are usually largest for people who are starting out.

Updated November 9, 2026.