VO₂ Max Estimator
Turn simple run tests into a VO₂ max category
VO₂ max, field tests and fitness level FAQ
What exactly is VO₂ max?
VO₂ max is an estimate of the maximum rate your body can use oxygen during hard exercise, usually expressed in millilitres of oxygen per kilogram of body mass per minute (ml/kg/min). Higher values generally track with better endurance performance and lower long-term risk from inactivity, but it is only one part of overall health.
How accurate are these VO₂ max estimates?
Direct lab tests that use masks and gas analysis are the reference standard. Field-test equations such as the Cooper 12-minute run or 1.5-mile / 2.4 km run are correlated but not perfect. They can be off by several ml/kg/min for an individual. Use them as a way to track trends and compare with population norms, not as a medical diagnosis or a hard ceiling on what you can do.
Why do age and sex change the VO₂ max category?
VO₂ max tends to peak in early adulthood and then gradually decline with age. On average, men also have higher VO₂ max values than women at the same fitness level, largely because of body size and haemoglobin differences. Normative tables adjust for age and sex so a given VO₂ can mean “excellent” in one group and only “fair” in another.
Which method should I pick if I have more than one?
If you have a recent lab test, that usually wins. If your only numbers are from a watch or treadmill, you can enter the VO₂ max they report and see how it lands in your age band. For runners without devices, a well-paced Cooper 12-minute run or timed 1.5-mile / 2.4 km effort on a measured track is often the simplest repeatable field test.
How often should I re-test my VO₂ max?
Most people only need to repeat a test every 4–8 weeks while they are actively training. Testing more often adds noise from day-to-day fatigue, weather, and pacing. Pick a method, run it under similar conditions, log the result in the summary, and watch the trend across months rather than obsessing over single numbers.
Does a higher VO₂ max automatically mean better health?
Higher cardiorespiratory fitness is linked with lower risk of heart disease, some cancers and premature mortality, but VO₂ max is not the only driver of health. Blood pressure, blood lipids, mental health, strength, sleep and lifestyle all matter. VO₂ max is best viewed as one useful vital-sign-like number to track alongside other markers that you and your clinicians follow.
Who should be careful with hard field tests?
People with known or suspected heart, lung or vascular disease, those with chest pain, unexplained shortness of breath, fainting or very high blood pressure should talk to a clinician before doing maximal or near-maximal run tests. In those cases, supervised testing or milder assessments can be safer than all-out efforts on your own.
How to use this VO₂ max estimator day to day
The goal of this page is to turn either a simple run test or an existing VO₂ number into a clear category for your age and sex. Instead of guessing whether a watch value is “good”, you can see where it falls and track how training, illness or breaks from exercise shift that category over time.
1. Choose a method you can repeat
If you already have a VO₂ max from a sports lab or a recent device estimate you trust, pick “I already know my VO₂ max” and enter the value in ml/kg/min. If not, choose either a Cooper 12-minute run (distance you can cover in 12 minutes) or a timed 1.5-mile / 2.4 km run on a measured track or path you can reuse later.
2. Enter units, age, sex and test details
First pick the unit system you think in: US (miles) or metric (km). That choice is used for run distances in the field tests. Then add your current age and sex so the tool can pull the right normative band. For a 12-minute test, enter total distance; for a 1.5-mile / 2.4 km test, type your finish time in minutes and seconds in the time bar.
3. Read the VO₂ max and fitness band
Hit Estimate VO₂ max to see:
- Your estimated VO₂ max in ml/kg/min.
- A simple fitness category (very poor to superior) for your age band.
- The method and units used, so you can recreate the same test and compare like with like.
The summary is designed to be copied into a notes app, training log or message to your coach so you can keep all tests in one place.
4. Track trends, not perfect scores
Small jumps up or down after a single test are often just noise. What matters most is the pattern across weeks and months. If your VO₂ max and category are improving while you feel better and your health markers are stable, you are probably on a good path. If VO₂ drops sharply or you feel worse despite training, that is a cue to back off, check recovery, and share the pattern with a professional.
Remember that no calculator replaces individual medical advice. Use this tool as a way to give structure to your training story, then let clinicians and coaches layer it with everything else they know about you.
How the VO₂ max formulas and bands work
Under the hood this calculator keeps things transparent: it converts your chosen test into a VO₂ max estimate in ml/kg/min, then lines that value up with age- and sex-specific bands drawn from published reference tables.
1. Direct VO₂ max entry
If you enter a known VO₂ max, the tool skips test equations and goes straight to classification. This is useful if you have a lab test or a watch that already reports VO₂ max and you simply want to know where that sits compared with typical values for your age and sex.
2. Cooper 12-minute run equation
For the Cooper test you run as far as possible in 12 minutes on a measured track or safe route. The original research related distance to VO₂ max with a simple linear formula. In this tool:
- Using miles (US): VO₂ max ≈ 35.97 × miles − 11.29.
- Using kilometres (metric): VO₂ max ≈ 22.35 × km − about 11.3.
Both give a value in ml/kg/min that is reasonably correlated with lab VO₂ max for many healthy adults performing the test all-out under standard conditions.
3. 1.5-mile / 2.4 km run time equation
For the timed 1.5-mile / 2.4 km effort, you enter how long it took to cover the distance at a strong but sustainable pace. A commonly used field equation is:
VO₂ max ≈ 3.5 + 483 ÷ time, where time is in minutes.
Faster times give higher VO₂ estimates. Because pacing, terrain, weather and experience all matter, this is still an approximation, but it can be very helpful for following changes after blocks of training.
4. Turning VO₂ max into fitness categories
Once the calculator has a VO₂ value, it uses tables derived from Cooper Institute-based normative data to assign a band (very poor, poor, fair, good, excellent, superior) for your age and sex. The boundaries are not magic cut-offs; they simply mark ranges where many people of a similar profile tend to fall. Being a little below or above a line does not fundamentally change your health picture, but it can be a nice benchmark when you look back on months or years of training history.
Because the research that shaped these equations mostly involved adults without serious disease, this page is best seen as a training and education helper. If your symptoms, medical history or test results worry you, the next step is always a conversation with your own healthcare team.
References and further reading on VO₂ max
These resources explain the field tests, equations and norms behind this tool:
- Normative VO₂ max tables by age and sex — summarises Cooper Institute-based reference values used to generate very poor to superior bands for men and women.
- Verywell Fit — Cooper 12-minute run test — describes the 12-minute run protocol and gives formulas that convert total distance into a VO₂ max estimate.
- Topend Sports — 1.5-mile / 2.4 km run VO₂ max test — outlines the timed run procedure and the common 3.5 + 483 ÷ time equation for estimating VO₂ max.
- REI Co-op — How to measure and improve VO₂ max — offers a practical overview of VO₂ max, what affects it and training ideas to raise aerobic fitness safely.
Use these for deeper background and share your test results with qualified professionals if you are using VO₂ max to guide medical decisions or high-risk training.