VO2 Max Estimate Calculator
Estimate your VO2 max from resting heart rate and age using the Uth-Sørensen formula.
A simple way to gauge your aerobic fitness level.
What Is VO2 Max?
VO2 max (maximal oxygen uptake) is the maximum rate at which your body can consume oxygen during intense exercise. It is measured in milliliters of oxygen per kilogram of body weight per minute (mL/kg/min) and is considered the gold standard measure of cardiorespiratory fitness.
Higher VO2 max values mean your heart, lungs, and muscles can work harder and more efficiently. Elite endurance athletes often have VO2 max values above 70 mL/kg/min. The average untrained adult typically falls between 30–45.
The Uth-Sørensen Formula
This calculator uses the Uth-Sørensen-Overgaard-Pedersen formula (2004), which estimates VO2 max from the ratio of maximum heart rate to resting heart rate:
VO2 max ≈ 15 × (HRmax ÷ HRrest)
Where:
- HRmax = Maximum heart rate = 220 − Age
- HRrest = Resting heart rate (measured in the morning before getting up)
VO2 Max Fitness Ratings by Age (Adults)
| Rating | Men (mL/kg/min) | Women (mL/kg/min) |
|---|---|---|
| Poor | Below 35 | Below 28 |
| Fair | 35–40 | 28–34 |
| Average | 41–48 | 35–41 |
| Good | 49–55 | 42–48 |
| Excellent | 56–62 | 49–55 |
| Elite | 63+ | 56+ |
Values for adults aged 20–39. VO2 max naturally declines about 1% per year after age 25.
How to Measure Resting Heart Rate
Take your pulse first thing in the morning, before getting out of bed. Count beats for 60 seconds — or count for 15 seconds and multiply by 4. For best accuracy, measure on 3 consecutive mornings and average the results. A healthy resting heart rate for adults is typically 60–80 bpm.
Improving Your VO2 Max
- High-intensity interval training (HIIT) is the most effective method
- Long slow distance (LSD) running or cycling also improves aerobic base
- Consistent training can improve VO2 max by 15–25% over several months