VO2 Max Calculator

How to use this tool

Pick the test you actually did, enter the result, then add your age and sex. The calculator converts the result to a VO2 max in millilitres of oxygen per kilogram of body weight per minute, then to METs, and places it against the FRIEND registry for your decade of age and sex, with the typical error of that test shown as a range. A race time goes through the Daniels and Gilbert equations and comes back with matching times for 5 km, 10 km, the half marathon and the marathon.

The two inputs that go wrong most often are the finishing heart rate in the Rockport walk and the unit in the Cooper test. Count your pulse for 10 seconds the moment you stop and multiply by 6, and check that the distance is set to metres or miles as you meant it. A time typed as 12:30 is 12 minutes 30 seconds, while 12.5 is read as decimal minutes.

What the calculation is doing

VO2 max is the most oxygen your body can take in and use in a minute, divided by your body weight. One MET is the oxygen use of sitting still, set at 3.5 mL/kg/min by convention, so METs are simply VO2 max divided by 3.5. A laboratory measures it with a mask during a test to exhaustion. Every method here estimates it from something easier to record.

• 1.5 mile run: VO2 max = 483 ÷ time in minutes + 3.5.
• Cooper 12 minute run: VO2 max = (distance in metres − 504.9) ÷ 44.73, which is the 1968 regression of distance on VO2 max turned around.
• Rockport walk: VO2 max = 132.853 − 0.0769 × weight in lb − 0.3877 × age + 6.315 for men − 3.2649 × time in minutes − 0.1565 × heart rate at the finish.
• Heart rate ratio: VO2 max = 15.3 × maximum heart rate ÷ resting heart rate.
• Race time, VDOT: the oxygen cost of your speed, −4.60 + 0.182258 v + 0.000104 v², divided by the fraction of VO2 max you can hold for the race duration, 0.8 + 0.1894393 e^(−0.012778 t) + 0.2989558 e^(−0.1932605 t), with v in metres a minute and t in minutes.

The fitness band comes from where the result falls among the 10th to 90th percentiles for your age and sex, and the range is one typical error either side.

Why the tests disagree with each other and with a lab

A laboratory measures oxygen use directly, so every method here is an estimate with a stated error, the standard error of estimate, which about two thirds of people fall within. The Cooper run carries ±3.6 mL/kg/min, derived from the variance printed in the 1968 paper on 115 US Air Force men, where the correlation was 0.897. The Rockport walk carries ±5.0. The heart rate ratio carries ±2.7 in 46 well trained men with a measured maximum, or ±4.7 with an age formula maximum. The 1.5 mile run carries ±5.3 in a study of 114 people, a figure that rests on one source.

The two running methods can disagree by more than a typical error. A 1.5 mile run in 11:40 gives 44.9 from the 1.5 mile equation and a VDOT of 37.8. The 1.5 mile equation is the ACSM running equation, 0.2 mL/kg/min for each metre a minute plus 3.5, applied to your average speed. Daniels fitted a lower oxygen cost to real runners: at 207 metres a minute it is 37.6 against 44.9. The two rest on different calibrations, and the size of the gap is a reminder that these are estimates.

So compare like with like: the same test to track your own progress, and only a rough placement against the FRIEND table, which used measured oxygen uptake. VDOT is a performance number. It assumes average running economy, so two runners with one VO2 max but different economy earn different VDOTs, and heat, hills and pacing move it. That is why the tool shows no error band for it.

The site's Pace Calculator predicts race times with Riegel's formula, time × (new distance ÷ old distance)^1.06. From a 20:00 5 km it gives 41:42 for 10 km, 1:32:00 for the half marathon and 3:11:49 for the marathon. VDOT gives 41:28, 1:31:50 and 3:11:17, which is 14, 11 and 32 seconds quicker. The race time mode shows both.

The same VO2 max in five tests

Read across a row to see what one VO2 max looks like in each test. A gap between your own results in two tests is normal, and the table shows how large a gap the equations themselves produce.

Cooper is the distance in 12 minutes. Rockport assumes a man aged 35 weighing 170 lb who finishes at 130 bpm, and Rest HR, in beats a minute, assumes a maximum of 190. Mile walks under about 10 minutes are close to race walking pace.

Fitness bands by age and sex, and why VO2 max matters

The bands come from the FRIEND registry: 7,783 maximal treadmill tests at eight US laboratories, 4,611 men and 3,172 women aged 20 to 79, none with known cardiovascular disease or chronic obstructive lung disease. VO2 max fell 9.2 percent per decade in men and 10.3 percent in women. The paper gives no category names, so Very low to Very high are this tool's labels for the ranges between percentile cut points, and "about the 55th percentile" is interpolated between them.

VO2 max percentiles in mL/kg/min from 7,783 maximal treadmill tests with measured oxygen uptake, FRIEND registry, Kaminsky and colleagues, 2015.

Fitness is worth knowing because it tracks health. In a 2009 JAMA meta analysis of 33 studies, each 1 MET higher fitness, about 1 km/h of running speed, went with a 13 percent lower risk of death from any cause (risk ratio 0.87, 95 percent interval 0.84 to 0.90). The risk of coronary or cardiovascular events was 15 percent lower (0.85, 0.82 to 0.88). Low fitness, under 7.9 METs or about 28 mL/kg/min, carried 1.70 times the mortality of high fitness, 10.9 METs or about 38 and above. These are observational associations, not proof.

What moves VO2 max

Age lowers it by about 10 percent a decade, and body weight matters because the figure is per kilogram. Training raises it. A meta analysis of interval training, 334 people in 37 studies, found an average gain of 0.51 L/min, about 6.8 mL/kg/min at 75 kg. The HERITAGE study put 481 sedentary adults through 20 weeks of training: the mean gain was about 400 mL/min, but some people gained almost nothing and others more than 1.0 L/min, and heredity explained up to 47 percent of the response.

A worked example you can check on paper

The default is a 1.5 mile run in 12:00 by a man aged 35. Twelve minutes gives 483 ÷ 12 + 3.5 = 40.25 + 3.5 = 43.75, shown as 43.8. In METs that is 43.75 ÷ 3.5 = 12.5. One typical error of ±5.3 gives 38.5 to 49.1.

For men aged 30 to 39 the 50th percentile is 42.4 and the 75th is 49.2, so 43.8 is above average. The percentile is 50 + 25 × (43.8 − 42.4) ÷ (49.2 − 42.4) = 55.1, about the 55th. The same man covering 2,400 m in the Cooper test scores (2,400 − 504.9) ÷ 44.73 = 42.4, 1.4 lower, well inside either error.

Mistakes that catch people out

Comparing a VDOT with a lab result. A VDOT of 37.8 and a 1.5 mile estimate of 44.9 can come from the same run. Compare a VDOT with earlier VDOTs, and a field test with the same test.

Guessing the finishing heart rate. In the Rockport walk each 10 beats a minute moves the estimate by 1.6. Take your pulse at once, since it falls fast, and note that beta blockers lower it and make the estimate read high.

Using a formula maximum in the heart rate ratio. Uth measured maximum heart rate in well trained men. In 634 middle aged men from the Kuopio study the ratio needed a multiplier of about 12, not 15.3, which turns 48.5 into 38.0. Treat this mode as a rough guide.

Treating a training run as a test. The 1.5 mile and Cooper equations assume a maximal effort on a flat, measured course, so a cautious first half or a headwind reads as lower fitness. Times slower than about 20:00 for 1.5 miles are closer to walking, where the Rockport test fits better.

Skipping the safety check. This page gives general information, not medical advice. A maximal test is hard work, so anyone with a heart condition, chest pain, dizziness or a long spell of inactivity should get medical clearance before trying one.

Popular calculations

Each opens the calculator with its own address, and every value can be changed once it is open.

1.5 mile run times

Cooper 12 minute run distances

Rockport one mile walk

Heart rate ratio

Race times, VDOT

How this was checked

The equations were coded in Node and compared with published numbers in 57 automated checks. The Cooper formula reproduces the class boundaries in the 1968 paper to within 0.4 mL/kg/min and is the printed regression, miles = 0.3138 + 0.0278 × VO2 max, inverted. The 1.5 mile formula returns 44.92 for the LibreTexts 11:40 example and matches the ACSM running equation to within 0.04 for runs of 6 to 25 minutes. The Rockport equation reproduces two published examples, 49.0 and 52.

The Daniels equations match the published VDOT tables at eight rows from VDOT 30 to 85 within 0.2 for 5 km times, and at VDOT 40 and 50 within 0.1 percent for 10 km, half marathon and marathon times. Solving for a time and back returns the starting VDOT at nine distances, and the Riegel figures match the Pace Calculator. All 60 FRIEND values match the paper's table, and the heart rate ratio constants and errors match the Uth abstract.

Every address in the lists above was loaded and checked for a distinct title, a matching canonical address and no missing values. The full Kline 1987 paper and the 2022 FRIEND update could not be opened, so the Rockport error rests on the 5.0 quoted by ExRx and the 0.325 to 0.355 L/min in the abstract.

Common questions

What is a good VO2 max?

It depends on age and sex, because VO2 max falls about 10 percent per decade. In the FRIEND registry the median is 42.4 for men aged 30 to 39 and 30.2 for women, and the 90th percentile is 56.5 and 41.4. Above the 75th percentile for your group is well above average.

How accurate is a VO2 max estimate from a run or a walk?

Within about ±3.6 to ±5.3 mL/kg/min for one standard error, which covers roughly two thirds of people. At a VO2 max of 45 that is 8 to 12 percent. The estimate is best used to track your own progress with the same test, not to settle a small difference between two people.

Which test should I use?

Use the 1.5 mile run or the Cooper test if you can run steadily for 12 minutes or more. The Rockport walk suits people who walk instead of run, and it was built on adults aged 30 to 69. The heart rate ratio needs a measured maximum heart rate. If you race, the race time is the easiest input.

What is VDOT, and is it the same as VO2 max?

VDOT is a score from Jack Daniels and Jimmy Gilbert that turns a race time into the VO2 max that would explain it for a runner of average economy. It is a performance number. A runner with poor economy has a VDOT below the lab VO2 max, and one with excellent economy has a VDOT above it.

How much can I raise my VO2 max?

A meta analysis of interval training in 334 people found an average gain of 0.51 litres a minute, about 6.8 mL/kg/min at 75 kg, and the response varies widely between people.

What is a MET?

One MET is the oxygen use of sitting quietly, set by convention at 3.5 mL/kg/min, so METs are VO2 max divided by 3.5. A VO2 max of 43.8 is 12.5 METs. Because the 3.5 is an average, not a measurement of you, treat METs as a unit of comparison rather than of your own metabolism.

Related Calculators and Reference

• Heart Rate Zone Calculator: gives the maximum heart rate the ratio method needs, and zones to train in once you know your level.
• Pace Calculator: turns a race time into a pace and predicts other distances with Riegel's formula, for comparing with VDOT.
• Calories Burned Calculator: uses METs, so your result here converts straight into energy for an activity.
• BMI Calculator: checks weight against height, which matters because VO2 max is divided by body weight.
• Steps to Miles Converter: helps you lay out an accurate mile for the Rockport walk.
• Mayo Clinic Proceedings: FRIEND reference standards for cardiorespiratory fitness: the source of the percentiles used for the fitness bands.