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Estimate your VO₂ max. Train with clearer numbers.

VO₂ max is the highest rate at which your body can use oxygen during hard exercise — a practical marker of aerobic fitness. Field tests give a useful estimate for tracking training, not a medical diagnosis. Lab gas analysis remains the gold standard when precision matters.

Open VO₂ max calculator What is VO₂ max?

Start with a method that fits you

Pick a hard run, a timed 1.5-mile effort, or a quiet resting heart-rate estimate.

VO₂ max calculator

Cooper, Uth–Sørensen resting HR, and 1.5-mile / 2.4 km formulas with live results.

Cooper 12-minute test

How to run it safely and convert distance into an estimate.

Heart-rate zones

Turn estimated HRmax into Z1–Z5 coaching ranges.

Improve VO₂ max

Practical zone work and consistency — no miracle language.

Clear, coach-like guidance

Disclaimer: Numbers from field tests are estimates. They are not the same as laboratory VO₂ max from expired-gas analysis, and they are not a medical diagnosis. Stop and seek care for chest pain, dizziness, unusual shortness of breath, or other warning signs.

Explore what VO₂ max means, how the Cooper test works, and common questions.

Training gear (affiliate)

Disclosure: Some links below are affiliate placeholders. If you buy through them later, we may earn a commission at no extra cost to you. We do not sell supplements.

Affiliate GPS running watch Track distance, pace & HR for field tests Affiliate Chest HR strap More stable resting & zone heart-rate readings Affiliate Road running shoes Comfortable footwear for Cooper / tempo runs