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METs calculator

Short answer

One MET is the oxygen you use sitting at rest: 3.5 mL per kg per minute. An activity's METs are its oxygen cost divided by 3.5, so 8 METs is 28 mL/kg/min. Because 1 MET is about 1 kcal per kg per hour, a 70 kg person at 8 METs burns about 9.3 kcal a minute.

Last reviewed 28 October 20263 published sourcesNot medical advice

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METs calculator

Convert between METs and oxygen uptake, and add your weight to see calories per minute.

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METs, oxygen uptake and calories
METsmL/kg/minkcal/min (70 kg)kcal/hour (70 kg)
1 MET3.51.270
3 METs10.53.5210
6 METs21.07.0420
8 METs28.09.3560
10 METs35.011.7700
12 METs42.014.0840
mL/kg/min = METs × 3.5; kcal per hour ≈ METs × body weight (kg).

From oxygen to METs to calories

One MET is the oxygen consumed while sitting at rest, 3.5 mL per kg per minute, and an activity's METs are its oxygen cost in mL/kg/min divided by 3.5 (Jetté, Sidney & Blümchen, 1990).

The 2024 Compendium of Physical Activities treats that resting rate as approximately 1.0 kcal per kg per hour, so energy ≈ METs × body weight (kg) × hours (Herrmann et al., 2024 (Compendium)).

The WHO classes 3 to under 6 METs as moderate activity and 6 or more as vigorous (Bull et al., 2020 (WHO)).

Find an activity's METs

The calories burned calculator lists Compendium MET values for common activities, and the heart rate calories calculator estimates a workout's calories from heart rate instead.

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Common questions

What is a MET?

A metabolic equivalent (MET) is the oxygen you use sitting at rest, defined as 3.5 mL of oxygen per kg of body weight per minute. An activity rated 6 METs uses six times that.

How do I convert METs to calories?

1 MET is approximately 1 kcal per kg per hour, so calories = METs × body weight (kg) × hours. Per minute, divide by 60.

How do I convert VO2 max to METs?

Divide by 3.5. A VO2 max of 42 mL/kg/min is 12 METs, which is how exercise stress tests often report fitness.

Sources

Figures on this page were checked against these publications on 28 October 2026.

  1. Jetté M, Sidney K, Blümchen G. Metabolic equivalents (METS) in exercise testing, exercise prescription, and evaluation of functional capacity. Clinical Cardiology. 1990;13(8):555–565. doi.org/10.1002/clc.4960130809
  2. Herrmann SD, Willis EA, Ainsworth BE, Barreira TV, Hastert M, Kracht CL, et al. 2024 Adult Compendium of Physical Activities: a third update of the energy costs of human activities. Journal of Sport and Health Science. 2024;13(1):6–12. doi.org/10.1016/j.jshs.2023.10.010
  3. Bull FC, Al-Ansari SS, Biddle S, et al. World Health Organization 2020 guidelines on physical activity and sedentary behaviour. British Journal of Sports Medicine. 2020;54(24):1451–1462. doi.org/10.1136/bjsports-2020-102955

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