What this calculator does
VO₂ max is the maximum rate at which your body can take in and use oxygen during exercise, expressed in millilitres per kilogram of body weight per minute. It is the standard measure of aerobic capacity and one of the better predictors of endurance performance.
The Cooper test estimates it from a simple field protocol: run as far as you can in 12 minutes. Developed for the US military in 1968, it remains popular because it needs nothing but a measured track and a watch, and it correlates well with laboratory testing when the effort is genuinely maximal.
The formula
The formula is a linear regression fitted to laboratory measurements against 12-minute run distances. It assumes a maximal, evenly paced effort: going out too hard and fading substantially will understate the result.
| Term | Meaning |
|---|---|
| VO₂ max | Millilitres of oxygen per kilogram of body weight per minute. |
| MET | VO₂ max ÷ 3.5, giving the maximum sustainable metabolic equivalent. |
| Cooper test | Maximum distance covered in 12 minutes of running. |
The inputs explained
| Field | What to enter |
|---|---|
| Distance run in 12 minutes (m) | Distance covered in 12 minutes, in metres. Run on a track or a flat measured route for an accurate figure. |
| Age (years) | Your age in years, used only for the rating comparison. |
| Sex | Biological sex, also used only for the rating comparison. |
When to use it
Establishing a fitness baseline
Run the test, record the result, and repeat every couple of months. The trend matters more than the absolute number, since the estimate carries a consistent bias for any given individual.
Comparing against typical values
The rating compares your result against averages for your age and sex. Aerobic capacity declines with age, so the comparison is age-adjusted rather than absolute.
Judging training progress
Improvements come mostly in the first months of consistent aerobic training and then slow considerably. A few points of gain over a season is a solid result for a trained runner.
Estimating sustainable work capacity
The METs figure indicates the highest intensity you can reach. Sustainable work sits well below maximum: typically 60 to 80 per cent for prolonged efforts.
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
VO₂ max at different 12-minute distances
Estimated aerobic capacity across a range of 12-minute run distances.
| 12-minute distance | VO₂ max | Rating | METs |
|---|---|---|---|
| 1.6 km | 24.5 ml/kg/min | Below average | 7.0 |
| 2.0 km | 33.4 ml/kg/min | Below average | 9.5 |
| 2.4 km | 42.4 ml/kg/min | Average | 12.1 |
| 2.8 km | 51.3 ml/kg/min | Good | 14.7 |
| 3.2 km | 60.3 ml/kg/min | Excellent | 17.2 |
| 3.6 km | 69.2 ml/kg/min | Excellent | 19.8 |
How the rating shifts with age
The same performance rated against typical values at different ages.
| Age | VO₂ max | Rating | Typical for your age & sex |
|---|---|---|---|
| 25 years | 46.8 ml/kg/min | Average | about 51 ml/kg/min |
| 32 years | 46.8 ml/kg/min | Average | about 47 ml/kg/min |
| 38 years | 46.8 ml/kg/min | Average | about 47 ml/kg/min |
| 45 years | 46.8 ml/kg/min | Good | about 43 ml/kg/min |
| 55 years | 46.8 ml/kg/min | Good | about 43 ml/kg/min |
| 65 years | 46.8 ml/kg/min | Good | about 43 ml/kg/min |
Questions
How accurate is the Cooper test?
Reasonably good when the effort is genuinely maximal and evenly paced, typically within about 10 per cent of laboratory measurement. Poor pacing, heat, wind or an uneven surface all degrade it.
What is a good VO₂ max?
It depends heavily on age and sex. Untrained adults commonly sit in the 30s, recreational runners in the 40s to low 50s, and elite endurance athletes above 70. The rating shown here compares against typical values for your age group.
How do I run the test properly?
Warm up thoroughly, then run as far as possible in exactly 12 minutes on a flat measured course, ideally a running track. Aim for even pacing: starting too fast is the most common way to understate the result.
Can I improve my VO₂ max?
Yes, particularly with consistent aerobic training and interval work. Gains are largest early on and then slow markedly, since a substantial portion is genetically determined.
Should everyone do a maximal test?
No. A maximal effort places real stress on the cardiovascular system. If you have a heart condition, high blood pressure, or are new to intense exercise, speak to a doctor before attempting one.
For training intensity bands, see heart rate zones. For pacing, use the running pace calculator.