VO₂max calculator (NTNU formula)
VO₂max is the maximum amount of oxygen your body can use per minute (ml/kg/min) and one of the strongest longevity markers.
How it is calculated
- 1It uses NTNU's non-exercise model from the HUNT Study: age, BMI, resting heart rate and an activity index are applied to a fixed intercept.
- 2Intercept: 100.27 for men, 88.72 for women. Each year of age −0.296; each BMI unit −0.552; each heart beat −0.135; each activity level +0.869.
- 3The activity index runs 0–5: sedentary 0, light 1.5, moderate 3, active 4, athlete 5.
- 4Without a resting heart rate, it is estimated from age, sex and activity, and the result is flagged as heart-rate estimated.
- 5The classification follows Cooper Institute / ACSM norms for age and sex.
Frequently asked questions
How accurate is the non-exercise formula?
In the HUNT Study the model estimated measured VO₂peak with a standard error of roughly 5 ml/kg/min. Individual results can differ from a lab test.
How do I measure resting heart rate?
Count your beats for 60 seconds in the morning before getting up, or use the resting heart rate from your smartwatch.
What is a good VO₂max?
It depends on age and sex. In your thirties, 47+ for men and 40+ for women counts as excellent.
How do I improve VO₂max?
Two to three interval sessions per week (for example 4×4 minutes) plus regular moderate cardio is the most effective route.
Sources
- Nes BM et al., Estimating VO2peak from a non-exercise prediction model: the HUNT Study, Norway (Med Sci Sports Exerc, 2011)
- NTNU World Fitness Level / Fitness Calculator
- WHO-5 Well-Being Index (WHO Regional Office for Europe)
- American Heart Association — Target Heart Rates & resting heart rate
- Cooper Institute / ACSM cardiorespiratory fitness norms
- WHO — Physical activity guidelines
This tool produces an estimate and is not a medical diagnosis. Talk to a doctor about health decisions.
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