Calculate an estimate of your VO2 max (maximal oxygen uptake) based on resting and max heart rate — without needing a physical fitness test.
The calculator uses the Uth-Sørensen-Overgaard-Pedersen formula, a non-exercise method for estimating maximal oxygen uptake from the ratio between max heart rate and resting heart rate:
The idea behind the formula is that the ratio between max heart rate and resting heart rate relates to your heart's stroke volume and thus your fitness level. A low resting heart rate relative to max heart rate normally indicates better fitness. The method is simple and requires no physical test, but is less accurate than directly measured VO2 max in an exercise physiology lab.
VO2 max is the maximal volume of oxygen your body can take up and use per minute under maximal effort, measured in milliliters of oxygen per kilogram of body weight per minute (ml/kg/min). It's considered one of the best measures of endurance fitness.
Measure your pulse right after waking up, while still lying still in bed, ideally over several days for a more stable average. Many fitness trackers and smartwatches measure this automatically overnight.
This formula only gives a rough estimate and is less accurate than a direct VO2 max test with gas analysis in an exercise physiology lab. It's still useful as a simple, non-strenuous starting point for tracking your own progress over time.