VO2 max calculator
VO2 max calculator: from a run, a walk or your heart rate.
- Method
- 12-minute run (Cooper)
- Published accuracy
- r = 0.897 in 115 men (Cooper 1968)
- Distance in 12 minutes
- 2.40 km (1.49 miles)
- Among US adults 30–39 (FRIEND)
- between the 25th and 50th percentiles
Run as far as you can in 12 minutes on a flat, measured course, such as a 400 m track, after a warm-up. Cooper’s equation came from 115 men; in other groups it has over- and underestimated.
For healthy adults 18 and over. An estimate, not a measurement or medical advice: field tests are off by several units. If you have a heart, lung or joint condition, are pregnant, or have been inactive and have symptoms, ask your doctor before a hard test.
This VO2 max calculator estimates your maximal oxygen uptake in ml/kg/min from Cooper’s 12-minute run, the Rockport one-mile walk or the ratio of your maximum to resting heart rate. It shows each test’s published accuracy and where your result sits among measured values for US adults your age.
- Free, no sign-up
- Kilometres or miles, kilograms or pounds
- Runs in your browser; nothing is saved
How the calculator works →Coaching clients? Try Trainaq free →
What is VO2 max?
VO2 max is the most oxygen your body can take in and use during hard exercise, given in millilitres per kilogram of body weight per minute. A laboratory measures it with a mask during a maximal treadmill or bike test. Field tests such as a 12-minute run or a one-mile walk estimate it, with an error of several units.
- Cooper’s 12-minute run (JAMA, 1968)
- The Rockport one-mile walk (Kline and colleagues, 1987)
- The heart rate ratio method (Uth and colleagues, 2004)
- Percentiles from the FRIEND registry of measured VO2 max
How it works
How does this VO2 max calculator work?
Pick a test you can do. The 12-minute run needs a measured course, the one-mile walk needs your heart rate at the end, and the ratio method needs your resting and maximum heart rates. The calculator applies that test’s published equation, shows its accuracy and compares the result with measured values for your age.
Choose a test
The run asks for a hard 12-minute effort. The walk is submaximal, so it suits people who can’t or shouldn’t run hard; it was built on adults aged 30 to 69. The ratio method needs no exercise test at all, only two heart rates.
- Run: the distance you cover in 12 minutes
- Walk: weight, time for the mile and heart rate at the end
- Ratio: resting and maximum heart rate
Do the test
For the run, warm up, then cover as much ground as you can in 12 minutes on a flat, measured course such as a 400 m track. For the walk, walk one mile as fast as you can without running and note your heart rate over the last quarter mile, as the study did.
- Kline’s volunteers walked the mile at least twice, and their fastest walks were used
- For the ratio method, take your resting rate lying still, ideally on waking
Read the estimate and its error
Each equation predicts the average person who scored like you. The calculator shows the error its study reported and where your estimate sits among the FRIEND registry’s measured values for your sex and age decade.
- FRIEND covers ages 20 to 79
Retest the same way
To track change, repeat the same test on the same course, at a similar time of day and in similar weather. A change of a few units can sit within the test’s own error, so look for a trend over several tests.
- Log each result so you can compare like with like
Formulas
Which formulas does the calculator use?
Cooper’s equation turns the distance covered in 12 minutes into VO2 max. Kline’s walk equation uses weight, age, sex, time and final heart rate to give litres a minute, which the calculator divides by your weight. Uth’s method multiplies the ratio of maximum to resting heart rate by 15.3.
VO2max = 22.351 × D − 11.288VO2 = 6.9652 + 0.0091 × W − 0.0257 × A + 0.5955 × S − 0.2240 × T − 0.0115 × HRVO2max = VO2 × 1,000 ÷ body weight in kgVO2max = 15.3 × HRmax ÷ HRrest- VO2max in ml/kg/min; D: distance in 12 minutes, in km (in miles: 35.97 × miles − 11.29)
- W: weight in pounds; A: age in years; S: 1 for men, 0 for women
- T: time for the mile in minutes; HR: heart rate over the last quarter mile
- HRmax and HRrest: maximum and resting heart rate, in beats a minute
Accuracy
How accurate is each VO2 max test?
Each is an estimate with an error of several units. Cooper’s run correlated 0.897 with treadmill VO2 max in his 115 men. Kline’s walk equation had a standard error of 0.325 litres a minute. Uth’s ratio method had 2.7 ml/kg/min in trained men, but agreed poorly with laboratory tests in a later study of older adults.
| Test | Built on | Published accuracy | Later findings |
|---|---|---|---|
| 12-minute run (Cooper 1968) | 115 US Air Force men | r = 0.897 with treadmill VO2 max | Overestimated by about 3 ml/kg/min in sedentary Indian students; low values under- and high values overestimated in young US adults |
| One-mile walk (Kline 1987) | 343 healthy adults aged 30–69 | SEE 0.325 L/min (r = 0.93); 0.355 L/min in the cross-validation group | About 4.3 ml/kg/min for a 75 kg person |
| Heart rate ratio (Uth 2004) | 46 well-trained men aged 21–51 | SEE 2.7 ml/kg/min (about 4.5%); 4.7 with an age-predicted maximum | Poor agreement with measured VO2 max in 20 adults averaging 62 years (Ducharme 2021) |
SEE: standard error of estimate; roughly two in three people fall within one SEE of their prediction. Sources: the studies’ abstracts; Bandyopadhyay (2015) and Penry (2011) for the later run findings.
Worked example
What does a worked example look like?
Take a 35-year-old man who runs 2.4 km in 12 minutes. Cooper’s equation gives 22.351 × 2.4 − 11.288 = 42.4 ml/kg/min. In the FRIEND registry, the middle value for men aged 30 to 39 is also 42.4, so he sits just under the 50th percentile, with the test’s error either side.
- A 40-year-old man, 80 kg, walking the mile in 15:00 with a final heart rate of 140: 3.17 litres a minute, or 39.6 ml/kg/min
- A 50-year-old woman, 65 kg, walking it in 16:30 with a final heart rate of 130: 1.79 litres a minute, or 27.6 ml/kg/min
- Resting heart rate 55, maximum 185: 15.3 × 185 ÷ 55 = 51.5 ml/kg/min
By age
What is a good VO2 max for my age?
Compare yourself with people of your age and sex. In the FRIEND registry of measured treadmill tests, the middle value for men falls from 48.0 ml/kg/min in their 20s to 24.4 in their 70s, and for women from 37.6 to 18.3. Above the 75th percentile means higher than three in four people your age.
| Age | Men, 25th–75th | Men, 50th | Women, 25th–75th | Women, 50th |
|---|---|---|---|---|
| 20–29 | 40.1–55.2 | 48.0 | 30.5–44.7 | 37.6 |
| 30–39 | 35.9–49.2 | 42.4 | 25.3–36.1 | 30.2 |
| 40–49 | 31.9–45.0 | 37.8 | 22.1–32.4 | 26.7 |
| 50–59 | 27.1–39.7 | 32.6 | 19.9–27.6 | 23.4 |
| 60–69 | 23.7–34.5 | 28.2 | 17.2–23.8 | 20.0 |
| 70–79 | 20.4–30.4 | 24.4 | 15.6–20.8 | 18.3 |
VO2 max in ml/kg/min by percentile, measured by cardiopulmonary exercise testing on a treadmill in 7,783 US adults without cardiovascular disease, 2014 to 2015 (Kaminsky 2015, Table 3). A field test carries its own error, so treat the comparison as approximate.
Limits
Why might my estimate differ from a laboratory test?
Field equations predict the average person who scores like you, and each fits the group it came from best: Cooper’s air force men, Kline’s adults aged 30 to 69, Uth’s trained men. How hard you push, your pacing and the course also move a run or walk result. A laboratory test with gas analysis measures VO2 max directly.
- Cooper’s equation overestimated measured VO2 max in sedentary Indian students (Bandyopadhyay 2015)
- In young US adults, the 12-minute run underestimated low values and overestimated high ones (Penry 2011)
- Uth’s method agreed poorly with laboratory tests in adults around 62 years old (Ducharme 2021)
Safety
Who should check with a doctor before these tests?
The run is a maximal effort and the walk is brisk, so check with your doctor first if you have heart, lung or joint problems or high blood pressure, are pregnant, or have been inactive and notice symptoms such as chest pain or unusual breathlessness. ACSM advises medical consultation and exercise testing when they are clinically indicated.
- Stop at once if you feel chest pain, dizziness or unusual breathlessness
- The ratio method needs no hard effort, but its maximum is an estimate unless measured
For coaches
How do coaches use VO2 max tests with clients?
Coaches use a field test as a repeatable benchmark. In Trainaq, add the 12-minute run or the one-mile walk to a client’s program as an exercise tracked by distance and time. The client logs the result in the free Trainaq app, and the workout player shows last time’s numbers when they repeat it.
- Write the test protocol in the exercise note, so every retest is run the same way
- Resting heart rate from Apple Health or Health Connect shows on the client’s progress, on Pro and Studio
- Ask how the test felt with your own question in the weekly check-in
Sources
Sources
- Cooper KH. A means of assessing maximal oxygen intake. Correlation between field and treadmill testing. JAMA. 1968;203(3):201–204.
- Bandyopadhyay A. Validity of Cooper’s 12-minute run test for estimation of maximum oxygen uptake in male university students. Biol Sport. 2015;32(1):59–63. (States Cooper’s equation as 22.351 × km − 11.288.)
- Penry JT, Wilcox AR, Yun J. Validity and reliability analysis of Cooper’s 12-minute run and the multistage shuttle run in healthy adults. J Strength Cond Res. 2011;25(3):597–605.
- Kline GM, Porcari JP, Hintermeister R, et al. Estimation of VO2max from a one-mile track walk, gender, age, and body weight. Med Sci Sports Exerc. 1987;19(3):253–259.
- Uth N, Sørensen H, Overgaard K, Pedersen PK. Estimation of VO2max from the ratio between HRmax and HRrest: the Heart Rate Ratio Method. Eur J Appl Physiol. 2004;91(1):111–115.
- Ducharme JB, Gibson AL. Efficacy of estimating VO2max with the Heart Rate Ratio Method in middle-aged and older adults. Eur J Appl Physiol. 2021;121(12):3431–3436.
- Kaminsky LA, Arena R, Myers J. Reference standards for cardiorespiratory fitness measured with cardiopulmonary exercise testing: data from the Fitness Registry and the Importance of Exercise National Database. Mayo Clin Proc. 2015;90(11):1515–1523.
- Garber CE, Blissmer B, Deschenes MR, et al. American College of Sports Medicine position stand. Quantity and quality of exercise for developing and maintaining cardiorespiratory, musculoskeletal, and neuromotor fitness in apparently healthy adults: guidance for prescribing exercise. Med Sci Sports Exerc. 2011;43(7):1334–1359.
FAQ
VO2 max calculator FAQ
Can I improve my VO2 max?
For most people, yes. To develop and keep cardiorespiratory fitness, ACSM recommends moderate cardio for at least 30 minutes on at least five days a week, or vigorous cardio for at least 20 minutes on three days. People respond to the same training very differently, so retest the same way to see your own trend.
Which VO2 max test is the most accurate?
Among these three, the ratio method had the smallest error in its own study, but only in well-trained men, and it agreed poorly in older adults later. The walk was built on a broad group of adults aged 30 to 69. Pick the test that suits you, then repeat that same test to track change.
Why does the calculator ask for my sex and age?
The walk equation uses both: at the same time and heart rate, it gives men a higher estimate and lowers it with age. The run and ratio methods leave them out, but the calculator uses your sex and age to compare your result with FRIEND’s measured values for people like you.
Do I need a heart rate monitor?
For the walk and the ratio method, yes. The walk equation uses your heart rate over the last quarter mile, and the study monitored heart rate continuously, so a chest strap or watch is the closest match. The ratio method needs a resting heart rate and, ideally, a maximum measured in a supervised test.
What units is VO2 max measured in?
Millilitres of oxygen per kilogram of body weight per minute, ml/kg/min, so people of different sizes can be compared. Kline’s walk equation first gives litres a minute for the whole body; the calculator multiplies by 1,000 and divides by your weight. Losing weight raises ml/kg/min even if the litres stay the same.
Does VO2 max fall with age?
On average, yes. In the FRIEND registry, measured VO2 max was about 10% lower with each decade of age across five decades, from people in their 20s to people in their 70s. That is why the calculator compares your result with your own age group and sex rather than with everyone.
