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Health & Fitness · Fitness

VO₂ Max Estimator

Estimate your VO₂ max from a Cooper run test or your resting heart rate, and see where it lands on a general fitness scale.

Estimation method
Time to run 1.5 miles
Try an example
Estimated VO₂ max
43.8ml/kg/minGood

Cooper 1.5-mile run test. Ratings are approximate and vary by age and sex.

RatingVO₂ max (ml/kg/min)
Poor< 30
Fair30–38
Goodyou38–45
Excellent45–52
Superior52+

These bands are a rough general guide for adults. True fitness percentiles depend on age and sex, so read the rating loosely.

VO₂ max is the most oxygen your body can use per minute, in millilitres per kilogram per minute (ml/kg/min). Using the Cooper 1.5-mile run test, VO₂max = (483 ÷ time) + 3.5. Run 1.5 miles in 12 minutes and that is 483 ÷ 12 + 3.5 ≈ 43.75 ml/kg/min — a good fitness level for most adults.

What VO₂ max is

VO₂ max (maximal oxygen uptake) is the highest rate at which your body can take in, transport, and use oxygen during all-out exercise. It is the single best measure of aerobic fitness: a higher VO₂ max means your heart, lungs, and muscles can supply more oxygen to keep you moving hard for longer. It is expressed relative to body weight, in millilitres of oxygen per kilogram of body weight per minute (ml/kg/min), so it is comparable between people of different sizes.

The gold-standard measurement is a graded exercise test in a lab, breathing into a mask while the treadmill speed rises to exhaustion. That is not practical for most people, so field tests estimate VO₂ max from how far or fast you can run, or from the ratio of your maximum to resting heart rate. This tool applies three of the standard estimation formulas — pick the one that matches the data you have.

Cooper 1.5-mile: VO₂max = (483 ÷ time_min) + 3.5 · Cooper 12-min: VO₂max = (distance_m − 504.9) ÷ 44.73 · Resting HR: VO₂max = 15.3 × (HRmax ÷ HRrest), HRmax = 220 − age

Three field estimates of VO₂ max in ml/kg/min. Time is in minutes; distance in metres; heart rates in bpm.

Worked example: 1.5 miles in 12:00

Suppose you run 1.5 miles and the clock reads 12 minutes flat. Here is how the Cooper 1.5-mile estimate falls out.

  1. 1
    Pick a method. Use a Cooper run test if you can measure a hard timed run; use the resting-heart-rate method if you only have your age and resting pulse.
  2. 2
    Gather the input. For the 1.5-mile test, run 1.5 miles as fast as you can and record the time — here, 12 minutes 0 seconds.
  3. 3
    Convert the time to minutes. 12 min 0 s = 12.0 minutes.
  4. 4
    Apply the formula. VO₂max = (483 ÷ 12.0) + 3.5 = 40.25 + 3.5 = 43.75 ml/kg/min.
  5. 5
    Read the rating. About 43.75 ml/kg/min lands in the “good” band for a general adult population — remember it shifts with age and sex.

Approximate VO₂ max fitness bands (adults)

A rough general guide in ml/kg/min. True percentile cut-offs depend heavily on age and sex, so treat these bands as approximate.

RatingVO₂ max (ml/kg/min)
Poor< 30
Fair30–38
Good38–45
Excellent45–52
Superior52+

How to read the estimate

Field-test formulas are estimates, not lab measurements. They assume a genuine all-out effort, good pacing, and flat ground, and each carries its own error — the resting-heart-rate method, in particular, leans on the rough 220 − age ceiling and can be off by several ml/kg/min. Use the same method each time so your trend is meaningful, even if the absolute number is imperfect. To raise VO₂ max, endurance athletes rely on a mix of easy aerobic volume and high-intensity intervals near maximum effort.

These numbers are estimated from field tests, not measured in a lab, and are for general information only — not medical advice. Check with a doctor before attempting a maximal-effort run, especially if you are new to exercise or have a heart condition.

What is a good VO₂ max?
For a general adult population, roughly 38–45 ml/kg/min is “good”, 45–52 is “excellent”, and above about 52 is “superior”. These bands are approximate: the true cut-offs drop with age and differ between men and women, so compare against people of your own age and sex.
How accurate are field-test estimates?
They are approximations, typically within a few ml/kg/min of a lab result when you run a genuine all-out effort. Pacing errors, hills, heat, and fatigue all skew the number, and the resting-heart-rate method adds the error of the 220 − age max-HR estimate.
Which estimation method should I use?
Use a Cooper run test (1.5-mile or 12-minute) if you can safely run hard and measure the time or distance — these track running fitness closely. Use the resting-heart-rate method if you only have your age and resting pulse; it needs no running but is the roughest of the three.
How can I improve my VO₂ max?
Combine a base of easy aerobic training with regular high-intensity intervals — repeated hard efforts of a few minutes near your maximum, with recovery between. Consistency over weeks matters most; VO₂ max responds to progressive endurance work but plateaus without harder sessions.
Why is VO₂ max measured in ml/kg/min?
It is the volume of oxygen (in millilitres) your body uses per minute, divided by your body weight in kilograms. Dividing by weight makes the figure comparable between a light and a heavy person, since a bigger body needs more absolute oxygen to do the same relative work.
Does VO₂ max fall with age?
Yes. VO₂ max peaks in the late teens to twenties and then declines gradually — often by around 10% per decade in inactive adults, though regular endurance training slows the drop substantially. That is why fitness ratings are always relative to age.
Why does the resting-heart-rate method use my resting pulse?
A lower resting heart rate generally reflects a stronger, more efficient heart. The formula VO₂max = 15.3 × (HRmax ÷ HRrest) rewards a bigger gap between your maximum and resting rates, so a fitter heart with a low resting pulse produces a higher estimate.