Calculators

VO2 Max Calculator

VO2 max is the most oxygen your body can use during hard exercise, in ml per kg per minute. Estimate it from your heart rate, or from how far you run in 12 minutes.

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Updated 16 October 2026
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VO2 max from your heart rate

With a maximum heart rate of 180, the heart rate ratio method gives:

Resting heart rate	Estimated VO2 max
50 bpm	55.1 ml/kg/min
60 bpm	45.9 ml/kg/min
70 bpm	39.3 ml/kg/min
80 bpm	34.4 ml/kg/min

A lower resting heart rate usually comes with fitness, which is why the estimate rises as it falls.

VO2 max from a Cooper test

Distance in 12 minutes	Estimated VO2 max
1,600 m (1.0 mile)	24.5 ml/kg/min
2,000 m (1.24 miles)	33.4 ml/kg/min
2,400 m (1.49 miles)	42.4 ml/kg/min
2,800 m (1.74 miles)	51.3 ml/kg/min
3,200 m (1.99 miles)	60.3 ml/kg/min

How we got it

Heart rate method (Uth and others, 2004): VO2 max = 15.3 x maximum heart rate / resting heart rate. Without a measured maximum we use 208 - 0.7 x age (Tanaka). In well-trained men it was within about 2.7 ml/kg/min on average with a measured maximum, or 4.7 with an age-based one; it is less tested in women and less fit people. Cooper test (Cooper, 1968): VO2 max = (metres covered in 12 minutes - 504.9) / 44.73. The plus or minus 10% band on the Cooper result is our own.

Updated 16 October 2026. Sources: Uth and others, 2004, European Journal of Applied Physiology; Cooper, 1968, JAMA.

The evidence

Every recommendation on this page links here. The badge shows what kind of source it is, so you can judge how strong it is.

Study
In well-trained men aged 21 to 51, VO2 max was about 15.3 times maximum heart rate divided by resting heart rate. Checked in 36 men, the typical error was 2.7 ml/kg/min with a measured maximum and 4.7 with an age-predicted one. The authors say other groups need their own validation.
Uth et al., 2004, European Journal of Applied Physiology: Estimation of VO2max from the ratio between HRmax and HRrest: the Heart Rate Ratio Method
Study
In 115 US Air Force men, the distance covered running in 12 minutes tracked treadmill-measured VO2 max closely (correlation about 0.90), the basis of the Cooper test.
Cooper, 1968, JAMA: A means of assessing maximal oxygen intake: correlation between field and treadmill testing
Review
A meta-analysis of 351 studies (18,712 people) gave maximum heart rate = 208 - 0.7 x age, confirmed in a lab study of 514 adults; 220 - age underestimates it in older adults.
Tanaka, Monahan and Seals, 2001, Journal of the American College of Cardiology: Age-predicted maximal heart rate revisited

Our own rules of thumb

These are our choices, not findings from a study. We list them so you know which parts are judgement calls.

The plus or minus 10% band on the Cooper estimate is our own.
Averaging your resting heart rate over 3 mornings.
Retesting every 2 to 3 months.

Questions

What is a good VO2 max?

Higher means more aerobic fitness. Typical values depend a lot on age and sex, and published norm tables differ, so the most useful comparison is with your own number a few months from now.

How accurate is a VO2 max calculator?

Only a lab test with a breathing mask measures VO2 max. In the heart rate method's own study the typical error was about 2.7 ml/kg/min with a measured maximum and 4.7 with an age-based one, roughly 5 to 8%.

How do I do the Cooper test?

After a good warm-up, run as far as you can in 12 minutes on a flat track or measured route, at a steady hard effort, and note the distance. Only do it if you are used to hard running.

How do I measure my resting heart rate?

Count your pulse for 60 seconds after waking, before you get up. Do it on 3 mornings and use the average.

Is my watch VO2 max accurate?

Watches use their own estimates from heart rate and pace. Treat the number as a trend: compare it with itself over weeks, not with a lab result.