What is a good VO2 max?

It depends on age and sex. As a rough guide, a fit adult male in their 30s is around 40–47 ml/kg/min and a fit female around 33–40 ml/kg/min. Elite endurance athletes often exceed 60. The calculator rates your result against age-and-sex norms.

How accurate is the resting heart rate method?

It is a quick estimate based on the ratio of maximum to resting heart rate, so it is less precise than a field or lab test. The Cooper and Rockport tests are generally more accurate because they measure real exercise performance.

How does the Cooper 12-minute run test work?

You run as far as you can in 12 minutes and enter the distance in metres. VO2 max is estimated as (distance − 504.9) ÷ 44.73. So 2400 m gives about 42.4 ml/kg/min.

What do I need for the Rockport walk test?

Walk one mile as fast as you can, then record your time and your heart rate at the finish, plus your weight, age and sex. The formula combines all five to estimate VO2 max, making it suitable for people who cannot run.

How is the resting heart rate estimate calculated?

It uses VO2 max ≈ 15.3 × (maximum HR ÷ resting HR), where maximum HR is estimated as 208 − 0.7 × age. A lower resting heart rate generally signals better aerobic fitness, so it raises the estimate.

Can I improve my VO2 max?

Yes. Regular aerobic and interval training can raise VO2 max over weeks to months, though genetics set an upper ceiling. Re-running the same test method periodically is the best way to track real change.

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VO2 Max Calculator — Gera Tools

VO2 max is the maximum rate at which your body can take in and use oxygen during intense exercise, measured in millilitres of oxygen per kilogram of body weight per minute (ml/kg/min). It is one of the best single markers of cardiovascular fitness and aerobic capacity. This calculator estimates it three ways — without any equipment, from a run, or from a walk — and rates the result against age-and-sex norms.

How it works

Pick the method that fits your situation; each uses a published estimation formula:

Resting heart rate (no test): VO2 max ≈ 15.3 × (HRmax / HRrest), where HRmax = 208 − 0.7 × age.
Cooper 12-minute run: VO2 max = (distance_metres − 504.9) / 44.73.
Rockport 1-mile walk: 132.853 − 0.0769×weight_lb − 0.3877×age + 6.315×(1 if male else 0) − 3.2649×walk_minutes − 0.1565×finishing_HR.

The result is then placed into Below average / Fair / Good / Excellent bands using ACSM-style norms for your age and sex.

Example

Using the Cooper test, a runner who covers 2400 m in 12 minutes gets:

VO2 max = (2400 − 504.9) / 44.73 = 1895.1 / 44.73 ≈ 42.4 ml/kg/min.

Method	Inputs	Estimated VO2 max
Cooper run	2400 m	~42.4
Cooper run	2800 m	~51.3
Resting HR	HRmax 187, rest 60	~47.7

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