What this calculator does
The Cooper test is a 12-minute run where the distance covered is used to estimate VO2 max, the maximum rate at which the body can use oxygen during exercise. It was developed as a field test that needs nothing but a measured track and a stopwatch, which is why it has stayed in use since the 1960s.
The estimate comes from a straight-line relationship fitted between test distance and laboratory measured VO2 max. Like any field estimate, it approximates a laboratory measurement rather than replacing it, and it assumes a genuinely maximal effort evenly paced across the full twelve minutes.
The formula
Subtract 504.9 from the distance covered in metres and divide by 44.73. The result is VO2 max in millilitres of oxygen per kilogram of body weight per minute. Multiplying by body weight converts it to an absolute figure in litres per minute.
| Term | Meaning |
|---|---|
| VO2 max | The maximum rate of oxygen uptake during exercise, in millilitres per kilogram of body weight per minute. A common measure of aerobic fitness. |
| Cooper test | A 12-minute maximal run where the distance covered is used to estimate VO2 max. |
| Absolute VO2 | The same figure expressed in litres per minute rather than per kilogram, which is more relevant where the body weight is being carried by equipment rather than the runner. |
The inputs explained
| Field | What to enter |
|---|---|
| Distance covered in 12 minutes (m) | The distance covered in twelve minutes, in metres. It needs to be a genuinely maximal, evenly paced effort for the estimate to mean anything. |
| Weight (for the oxygen figure) (kg) | Body weight in kilograms, used only to convert the result into an absolute oxygen uptake figure. |
When to use it
Tracking fitness over time
Repeating the same test under similar conditions makes the change between tests the useful figure, which is more reliable than the absolute estimate.
Comparing against a training plan
Many running plans set paces from a VO2 max estimate, and the Cooper test is a way to get one without a laboratory.
Checking a wearable estimate
Watches estimate VO2 max from heart rate and pace. A field test gives an independent figure to compare, though neither is a laboratory measurement.
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.
What VO2 max does each Cooper test distance suggest?
A range of distances covered in the twelve minutes.
| Distance in 12 minutes | Estimated VO2 max | Average pace in the test |
|---|---|---|
| 1,600 m | 24.5 mL/kg/min | 7:30 per km |
| 2,000 m | 33.4 mL/kg/min | 6:00 per km |
| 2,400 m | 42.4 mL/kg/min | 5:00 per km |
| 2,800 m | 51.3 mL/kg/min | 4:17 per km |
| 3,200 m | 60.3 mL/kg/min | 3:45 per km |
Questions
How accurate is the Cooper test?
It is an estimate from a fitted relationship, so it carries real error against a laboratory measurement. Pacing, motivation, surface, wind and temperature all move the distance covered without changing the underlying fitness, which is why the trend across repeated tests is more informative than a single result.
Should I do this test?
It is a maximal effort by design, which is not appropriate for everyone. Anyone new to exercise, returning after a break, or with a heart or respiratory condition should speak to a doctor before attempting a maximal test.
Why does body weight not affect the main figure?
VO2 max is already expressed per kilogram, so weight is built into the unit. The absolute figure in litres per minute is the one that uses weight directly, and it is the more relevant version where the body weight is supported rather than carried.
Is a higher VO2 max always better?
It is one measure of aerobic capacity, and it correlates with endurance performance without determining it. Running economy, pacing and durability all matter, which is why runners with similar VO2 max figures often race quite differently.
For training zones from heart rate rather than oxygen uptake, see the target heart rate calculator. For race pacing, see the running pace calculator.