VO2max Calculator
VO2max Calculator
Estimate your VO2max, the single best number for cardiorespiratory fitness and long-term health, without a lab test. Just your resting heart rate, a few basics, and how you train.
Your pulse at rest. Don't know it? Measure it free in 60 seconds with our face-age scan.
Fill in the form to see your VO2max estimate
This calculator gives a population-based estimate for healthy adults and is for education, not medical advice. Non-exercise estimates are least accurate at the extremes of fitness. Talk to a doctor before starting vigorous exercise if you have a heart condition or have been inactive.
Medical disclaimerThis tool estimates your VO2max (maximal oxygen uptake) from the validated HUNT non-exercise model: age, sex, resting heart rate, body measurement and how much you train. VO2max is one of the strongest predictors of long-term health and mortality. Because it is a self-report estimate, treat it as a screening number (about ±5 to 6 ml/kg/min), not a lab measurement, and use the face-age scan to get an accurate resting heart rate.
What VO2max is, and why it matters
VO2max is the maximum amount of oxygen your body can use during hard exercise, measured in millilitres per kilogram of bodyweight per minute (ml/kg/min). It is the best single measure of cardiorespiratory fitness, and one of the strongest predictors of all-cause mortality: higher fitness tracks with a longer, healthier life. A true VO2max needs a lab test with a mask and a treadmill, while this tool estimates it instead from things you already know.
Why resting heart rate (and the face-age scan)
A lower resting heart rate generally reflects a stronger, more efficient heart, which is why the HUNT model uses it as an input [1]. It is not the biggest driver (your age, body composition and especially how hard you train matter more), but it sharpens the estimate. If you don't know your resting heart rate, our face-age scan measures it from your webcam in about 60 seconds and hands it straight to this calculator.
Run the face-age scanHow accurate is a non-exercise estimate?
The HUNT model explains roughly 56 to 61% of the variation in measured VO2max, with a standard error of about 5 to 6 ml/kg/min [1, 4]. That is close to other non-exercise equations and good enough to place you in a fitness band, but not a substitute for a lab test. It tends to overestimate fitness in inactive people and underestimate it in well-trained athletes, so read your result as an orientation, not a verdict. The height-and-weight (BMI) and waist versions are about equally accurate [1, 2]; waist is marginally better.
How to move the number
VO2max responds to training. The biggest lever in this model, and in real life, is intensity: sessions hard enough to leave you breathing heavily. A mix of longer easy aerobic work and short, hard intervals raises VO2max over weeks to months. Losing excess weight around the middle and lowering a high resting heart rate through consistent aerobic training both nudge the estimate up too.
How this calculator works
No treadmill, no mask. Five inputs and one well-validated equation.
- 1You enter your sex, age, resting heart rate, body measurement (height and weight, or waist), and how you train.
- 2We combine your training frequency, session length and intensity into a single physical-activity index, exactly as the HUNT study does [1].
- 3We feed those into the HUNT non-exercise equation [1], the only validated model that uses your resting heart rate, to estimate your VO2max.
- 4We place that number on the FRIEND reference percentiles for your age and sex [3] to give you a fitness level and a fitness age.
- 5We show the estimate as a range, because a self-report model carries about ±5 to 6 ml/kg/min of uncertainty [4].
Read this as an estimate
Every input here is self-reported, and self-reported activity in particular tends to run optimistic, which biases the estimate upward. The model is most accurate for ordinary, middle-fitness adults and least accurate at the extremes. Use it to track your own trend over time rather than to compare yourself precisely to someone else, and if you want a real number, a graded exercise (CPET) test at a sports-medicine clinic is the gold standard.
Frequently asked questions
Can you really estimate VO2max without a treadmill test?
Yes, within limits. Non-exercise models like the HUNT equation [1] estimate VO2max from your age, sex, resting heart rate, body composition and activity level, and explain about 56 to 61% of the variation in measured VO2max [1, 4]. That is accurate enough to tell which fitness band you are in, but not a replacement for a lab (CPET) test, which stays the gold standard.
What is a good VO2max for my age?
It depends on age and sex. We place your estimate on the FRIEND treadmill reference percentiles [3]: roughly, above the 80th percentile for your age and sex is excellent, around the 50th is average, and below the 20th is poor. A 40-year-old man near 48 ml/kg/min sits around average; a woman near 38. Fitness declines with age, so the bands shift down each decade.
How does resting heart rate affect the estimate?
A lower resting heart rate usually means a fitter, more efficient heart, and the HUNT model uses it as one input [1]. It is a helpful signal but not the main driver: your activity level and body composition matter more. You can measure your resting heart rate free with our 60-second face-age scan and bring it straight here.
Should I enter waist or height and weight?
Either works. The original HUNT model uses waist circumference [1]; a validated version swaps in BMI from height and weight [2], and the two are about equally accurate. Height and weight are easier to report accurately, so we default to them; add your waist if you have a tape measure and want the original model.
Why is my estimate a range, not one number?
Because the model has real uncertainty of about ±5 to 6 ml/kg/min, one standard error [1, 4]. Showing a single decimal would imply a precision the method does not have. Treat the midpoint as your best estimate and the range as where your true value probably sits.
How can I improve my VO2max?
Train your aerobic system, and don't skip intensity. A combination of easy aerobic volume and short, hard intervals raises VO2max over weeks to months. Lowering a high resting heart rate and reducing excess waist fat both help the estimate too. Consistency beats any single hard session.
Sources
The equation and the reference percentiles come from these peer-reviewed sources.
- Nes BM, Janszky I, Wisløff U, Støylen A, Karlsen T (2011). Estimating V̇O2peak from a nonexercise prediction model: the HUNT Study, Norway. Medicine & Science in Sports & Exercise. doi:10.1249/MSS.0b013e31821d3f6f
- Jalene S, Cross C, Daniel D, Mendez K, Pollard MS, Jalene P (2019). Cardiorespiratory fitness is associated with reported depression in college students. Frontiers in Physiology. doi:10.3389/fphys.2019.01191
- Kaminsky LA, Arena R, Myers J (2015). Reference standards for cardiorespiratory fitness measured with cardiopulmonary exercise testing: data from the FRIEND registry. Mayo Clinic Proceedings. doi:10.1016/j.mayocp.2015.07.026
- Loe H, Nes BM, Wisløff U (2016). Predicting VO2peak from submaximal- and peak exercise models: the HUNT 3 Fitness Study, Norway. PLoS ONE. doi:10.1371/journal.pone.0144873
Don't know your resting heart rate?
Measure it free in about 60 seconds with our face-age scan. It reads your pulse from your webcam and sends it straight to this calculator.