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Your VO2max from a simple field test.

Estimate your maximal oxygen uptake with three proven non-lab tests — Rockport Walk Test, 1.5-Mile Run, or Cooper 12-Minute Run — and see your fitness category by age and sex.

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VO2max — Maximal Oxygen Uptake
Estimate aerobic capacity from Rockport Walk, 1.5-Mile Run or Cooper 12-Min Run
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Your data

yr
lb
min
sec
bpm
min
sec
mi
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Your result

— mL/kg/min
—
Enter your test data above
VO2max estimate—
Fitness category percentile vs HUNT 3, your age & sex—
Method used—

How it's calculated

Three field tests, one aerobic fitness number

VO2max (maximal oxygen uptake) is the maximum rate at which your body consumes oxygen during intense exercise, expressed in mL per kg of body weight per minute. This calculator supports three validated non-lab tests: the Rockport 1-Mile Walk Test (Kline et al., 1987), the 1.5-Mile Run Test (ACSM), and the Cooper 12-Minute Run Test (Cooper, 1968). For a 35-year-old male walking 1 mile in 15 min at 130 bpm and 165 lb, estimated VO2max is about 43.6 mL/kg/min — roughly the 23rd percentile for men aged 30–39, a fair result.

Each formula uses a different set of inputs but all estimate the same underlying aerobic capacity. Rockport is best for those who cannot run safely; the 1.5-Mile and Cooper tests require all-out effort for maximum accuracy. All results are estimates; lab treadmill VO2max testing remains the gold standard.

Rockport (Kline 1987)
132.853 − (0.0769 × weight_lb) − (0.3877 × age) + (6.315 × sex_M)
− (3.2649 × time_min) − (0.1565 × HR_bpm)

1.5-Mile Run (ACSM)
3.5 + 483 ÷ time_minutes

Cooper 12-Min Run
(distance_m − 504.9) ÷ 44.73

Fitness category
z = (your VO2max − mean) ÷ SD, for your age group and sex
percentile = Φ(z) × 100

Where the categories come from. The mean and standard deviation are the published values of the HUNT 3 Fitness Study, which measured VO2max directly in 3,816 healthy adults aged 20–90. The study reports those reference values but does not define fitness categories, so the bands are ours and we state them plainly: poor below the 20th percentile, fair from the 20th to the 59th, good from the 60th to the 84th, excellent from the 85th up. Two caveats worth knowing: HUNT is a Norwegian sample of healthy adults, fitter than the general population, so the percentiles here are demanding; and the study starts at age 20, so below that we use the 20–29 group and say so in the result.

  1. 1
    Convert inputs to formula units
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  2. 2
    Apply the selected formula
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  3. 3
    Clamp result to valid range (10–85 mL/kg/min)
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  4. 4
    Compare with the HUNT 3 reference for your age & sex
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Understand the terms

VO2max
The maximum rate of oxygen consumption during maximal effort exercise. The gold-standard measure of aerobic fitness, expressed in mL O₂ per kg bodyweight per minute (mL/kg/min).
Aerobic capacity
The ability of the cardiovascular and respiratory systems to supply oxygen to working muscles. VO2max is its most common quantitative measure.
Maximal oxygen uptake
Synonymous with VO2max. Determined by cardiac output (heart rate × stroke volume) and the muscles' ability to extract oxygen from blood.
Lactate threshold
The exercise intensity at which lactic acid begins to accumulate faster than it is cleared. Typically occurs at 50–80% of VO2max in trained individuals. Endurance performance depends strongly on both VO2max and lactate threshold.
See the full glossary →

🔢 Worked example

In the Cooper test, running 2,400 m in 12 min: VO₂max = (2,400 − 504.9) ÷ 44.73 ≈ 42 ml/kg/min.

Disclaimer: estimation tool for informational and planning purposes, using validated field-test equations (Kline et al. 1987, ACSM, Cooper 1968). Estimated VO2max may differ from a laboratory-measured value. Results depend on test execution — pacing, surface, weather, and heart rate measurement all affect accuracy. Does not replace assessment by a physician, exercise physiologist, or sports scientist.

Frequently asked questions — VO2max

What is VO2max?
VO2max is the maximum rate at which your body can consume oxygen during intense exercise. It is expressed in mL of oxygen per kilogram of body weight per minute (mL/kg/min) and is considered the gold standard measure of aerobic fitness and cardiovascular endurance. Higher VO2max values correspond to greater endurance performance capacity.
What is a good VO2max score?
Norms vary by age and sex, so the same number means different things at 25 and at 60. This calculator compares your result with the HUNT 3 Fitness Study, which measured VO2max directly in 3,816 healthy adults and published the mean and standard deviation for each age group and sex. For men aged 30–39 the average is 49.1 mL/kg/min, and on our bands a result is good from about 51 and excellent from about 57. For women in the same age group the average is 40.0, good from about 42 and excellent from about 47. Elite endurance athletes often exceed 70–80 mL/kg/min. Note that HUNT is a Norwegian sample of healthy adults, fitter than the general population, so percentiles here are demanding.
How does the Rockport Walk Test work?
You walk exactly 1 mile (1.6 km) as fast as possible on a flat, measured surface, then record your total time and heart rate immediately at the finish. The Kline et al. (1987) formula uses your age, sex, weight, walk time, and finishing heart rate to estimate VO2max. It is ideal for people who cannot safely run due to injury or fitness level.
What is the Cooper 12-minute run test?
Developed by Dr. Kenneth Cooper in 1968, the Cooper Test requires you to run or jog as far as possible in exactly 12 minutes on a flat surface. The distance covered is then plugged into the formula: VO2max ≈ (distance in metres − 504.9) ÷ 44.73. It is widely used by the military, police forces, and sports organizations worldwide because it requires minimal equipment.
Can I improve my VO2max?
Yes. VO2max is highly trainable. High-intensity interval training (HIIT), tempo runs at lactate threshold, and progressive aerobic volume all stimulate improvements. Sedentary individuals who begin structured training often see 10–20% gains within 8–12 weeks. Genetics set an upper limit, but consistent cardio training can substantially raise your aerobic capacity at any age.
Are my results saved? Do I need an account?
No account or sign-up needed. Every calculation is saved automatically in your own browser, and you can also pin a result with the save button. Nothing is sent to any server: the data stays on your device and can be erased at any time with the clear button.
How do I track my progress over time?
From the fourth entry onward a “View comparison chart” button appears, opening a line chart with every entry in time order plus an indicator panel: total change, average per entry, lowest and highest value and the period covered. You can also export the history as CSV.

📚 Learn more — official sources

🔬 Study HUNT 3 Fitness Study (Loe et al., 2013) — VO2max reference data Open-access reference values used for the fitness category on this page: VO2max measured directly in 3,816 healthy adults aged 20–90, with mean and standard deviation per age group and sex. PLoS ONE 8(5):e64319. See official source → 🔬 Study Kline et al. (1987) — Rockport Walk Test original paper Original validation study of the 1-mile walk test equation for estimating VO2max from walk time, heart rate, weight, age, and sex. See on PubMed → 🔬 Study Cooper (1968) — A means of assessing maximal oxygen intake Landmark paper by Dr. Kenneth Cooper establishing the 12-minute run test and its correlation with measured VO2max in over 100 men. See on PubMed → 🏛️ Organization WHO — Physical activity fact sheet World Health Organization guidance on physical activity levels, aerobic fitness, and health benefits of cardiorespiratory endurance training. See official source →

🔄 Page last reviewed: July 2026. Laws and standards cited keep their original publication year; the date above is when the content and the calculation were reviewed.

About the VO2max Calculator

VO2max — maximal oxygen uptake — is the most widely used measure of cardiorespiratory fitness. Lab measurement requires a treadmill, gas analysis equipment, and a physician-supervised protocol. These three validated field tests let anyone estimate VO2max with minimal equipment: a measured course, a stopwatch, and a heart rate monitor (for Rockport).

The Rockport Walk Test (Kline et al., 1987) is ideal for beginners and older adults. The 1.5-Mile Run Test is a standard protocol used by the U.S. Armed Forces and ACSM. The Cooper 12-Minute Run is one of the most replicated fitness tests in history. All three produce estimates within ±5 mL/kg/min of lab-measured VO2max under controlled conditions.

By Vinicius Fonseca · Formulas checked against scientific sources · Updated Jul 2026 · How we calculate →