VO2 Max Calculator: Estimate Your VO2 Max and Fitness Age Without a Test

This VO2 max calculator estimates your cardiorespiratory fitness and your fitness age without a treadmill test. Answer six quick questions about your age, size, resting heart rate and exercise habits, and it applies a published research model to estimate your VO2 max and the age your fitness matches. If you can walk a mile, an optional walk test compares you with US adults your age.

What VO2 max and fitness age mean

VO2 max is the most oxygen your body can use during all-out exercise, measured in milliliters per kilogram of body weight per minute (mL/kg/min). It is the standard measure of cardiorespiratory fitness: how well your heart, lungs and muscles work together. Our guide to VO2 max and how to improve it covers it in depth.

Fitness age turns that number into something easier to picture. It is the age at which an average healthy adult in the reference study has the same fitness as you. A 55-year-old with a fitness age of 45 is as fit as a typical 45-year-old.

How the calculator works

The main result uses the non-exercise fitness model developed by the Cardiac Exercise Research Group at the Norwegian University of Science and Technology (NTNU), built and tested in the HUNT study of Norwegian adults (1, 2). It predicts VO2 max from:

• your age and sex
• your body mass index, from your height and weight
• your resting heart rate
• how often, how long and how hard you exercise

Your fitness age is then read from the study’s age-expected fitness lines. We use the corrected equation for women, which was revised in a 2020 published correction (3). We implemented the published equations independently; The Wonder Drop has no affiliation with NTNU.

The optional walk test uses the Rockport one-mile walk equation, built on 343 adults aged 30 to 69 who walked a timed mile (4). Because it uses a real effort, it is a better way to track your progress over time.

What is a good VO2 max for your age?

The table shows the median (50th percentile) VO2 max measured on a treadmill in healthy US adults in the FRIEND registry, the largest US reference dataset (5). Being above the median for your age and sex means you are fitter than most people your age.

Values are in mL/kg/min. Norwegian adults in the HUNT study are fitter than these US averages at every age, which is why the walk test, compared with US data, and the fitness age, compared with Norwegian data, are shown separately and won’t match.

Why your fitness age matters

Cardiorespiratory fitness is one of the strongest predictors of how long you live. A meta-analysis of 33 studies in about 100,000 healthy adults found that each 1-MET higher fitness level, about 3.5 mL/kg/min, went with 13% lower risk of death from any cause and 15% fewer cardiovascular events (6). In a study of more than 120,000 adults who had a treadmill test, below-average fitness carried a higher risk of death than above-average fitness, about as large as the risk linked to smoking or diabetes in the same study (7).

The NTNU model behind this calculator was itself tested this way. Among 37,112 Norwegians followed for up to 24 years, each 1-MET higher estimated fitness went with 21% lower risk of cardiovascular death (1). These are associations from observational studies, not proof that changing your number will add years, but they are consistent and large.

How accurate is a VO2 max estimate without a test?

Any estimate from a questionnaire is rough. The original HUNT model’s typical error is about 5 to 6 mL/kg/min, which is roughly 15 years of fitness age either way (2). In a large US cohort, the model overestimated measured fitness on average, and non-exercise equations in general were poor at tracking small changes over time (8). Use your result as a ballpark, and use the walk test or a lab test to measure progress.

The estimate is not suitable if you take medicine that lowers your heart rate, such as a beta blocker, because a lower resting pulse makes you look fitter than you are. It is also less reliable for people with heart or lung disease or an irregular heartbeat, during pregnancy, and for competitive endurance athletes.

How to lower your fitness age

1. Build an aerobic base. Two to four sessions a week of easy, conversational cardio. Our Zone 2 heart rate calculator gives you the right pace.
2. Add one harder session a week once you are comfortable, such as intervals. A meta-analysis of 28 studies found that steady endurance training and intervals both raise VO2 max substantially, with intervals adding a small extra gain (9).
3. Exercise more often, for longer. In the model, moving from rare exercise to two or three 30-minute sessions a week that make you breathe harder lowers your fitness age noticeably.
4. Keep strength training two days a week. Our free workout plan generator builds a plan with cardio days included.

If you have chest pain, unusual breathlessness, fainting or palpitations, see a doctor before exercising hard. See our medical disclaimer.

Sources

1. Nes BM, Vatten LJ, Nauman J, Janszky I, Wisløff U. A simple nonexercise model of cardiorespiratory fitness predicts long-term mortality. Med Sci Sports Exerc. 2014;46(6):1159-1165. PubMed 24576863
2. Nes BM, Janszky I, Vatten LJ, et al. Estimating VO2peak from a nonexercise prediction model: the HUNT Study, Norway. Med Sci Sports Exerc. 2011;43(11):2024-2030. PubMed 21502897
3. Correction to: Left atrial volume, cardiorespiratory fitness, and diastolic function in healthy individuals: the HUNT Study, Norway. J Am Heart Assoc. 2020. PMC7763422
4. 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. PubMed 3600239
5. Kaminsky LA, Arena R, Myers J, et al. Updated reference standards for cardiorespiratory fitness measured with cardiopulmonary exercise testing: data from the Fitness Registry and the Importance of Exercise National Database (FRIEND). Mayo Clin Proc. 2022;97(2):285-293. PubMed 34809986
6. Kodama S, Saito K, Tanaka S, et al. Cardiorespiratory fitness as a quantitative predictor of all-cause mortality and cardiovascular events in healthy men and women: a meta-analysis. JAMA. 2009;301(19):2024-2035. PubMed 19454641
7. Mandsager K, Harb S, Cremer P, et al. Association of cardiorespiratory fitness with long-term mortality among adults undergoing exercise treadmill testing. JAMA Netw Open. 2018;1(6):e183605. PubMed 30646252
8. Peterman JE, Harber MP, Imboden MT, et al. Accuracy of nonexercise prediction equations for assessing longitudinal changes to cardiorespiratory fitness in apparently healthy adults: BALL ST cohort. J Am Heart Assoc. 2020;9(11):e015117. PubMed 32458761
9. Milanović Z, Sporiš G, Weston M. Effectiveness of high-intensity interval training (HIT) and continuous endurance training for VO2max improvements: a systematic review and meta-analysis of controlled trials. Sports Med. 2015;45(10):1469-1481. PubMed 26243014