Calories burned calculator
One MET is defined as 3.5 millilitres of oxygen per kilogram per minute, and that number was taken from the resting oxygen consumption of a single person: a 70 kg, 40-year-old man. When Byrne and colleagues measured resting rate in 769 adults, the average was 2.6 ml/kg/min. Against that sample the 3.5 convention overstates resting oxygen use by about 35%, and the 1 kcal/kg/hour version overstates resting energy expenditure by about 20%. Every MET figure on this page inherits that.
MET values are population averages resting on a constant derived from one person in the 1950s. Individual expenditure varies with fitness, efficiency, terrain and body composition, and wearable estimates are frequently 20–30% out in the other direction. Read any of these figures as an order of magnitude, not a measurement.
Calories burned are MET × 3.5 × weight in kg ÷ 200, per minute. Jogging at MET 7 for 45 minutes at 75 kg gives about 413 kcal, or roughly 54 grams of body fat at the usual 7,700 kcal per kilogram. The arithmetic is simple and the constant underneath it is shakier than it looks.
How to estimate calories burned
A MET is a multiple of resting metabolic rate, and the whole system hangs on what one MET is worth. It is defined as 3.5 millilitres of oxygen per kilogram per minute, a value taken in the 1950s from the resting oxygen consumption of one person, a 70 kg 40-year-old man. In 2005 Byrne and colleagues measured resting rate by indirect calorimetry in 642 women and 127 men, aged 18 to 74 and weighing between 35 and 186 kg. The average came out at 2.6 ml/kg/min, not 3.5. Against that sample the standard MET value overstates resting oxygen use by roughly 35%, and the kcal-per-kilogram-per-hour form overstates resting energy expenditure by about 20%. Body composition explained 62% of the variation in resting oxygen use; age explained 14%. The convention is a reasonable fit for a lean man of average age and a poor one at the edges.
On top of that, these are gross figures. They include the energy you would have spent anyway simply by existing for the length of the session, and the panel gives you that number for free: one MET is 3.5 × your weight ÷ 200 kcal a minute, which at the 75 kg default is 1.31, so the 45-minute session on the defaults carries about 59 kcal you would have burned sitting down. The additional cost of the session is the headline minus that. Note that it scales with the duration you entered rather than with the hour: the same arithmetic over a full sixty minutes gives 79 kcal, which is where the familiar "roughly 75 an hour at rest" comes from. Subtracting the hourly figure from a 45-minute session overstates the correction by a third.
The obvious alternative is worse. Independent testing of consumer wearables routinely finds energy expenditure errors of 20 to 30 per cent, on devices whose heart rate tracking is perfectly good, because inferring calories from heart rate requires assumptions the device cannot check. The MET method has the advantage of stating its assumptions out loud, which is the only real claim being made for it here.
One row deserves a warning label. The step equivalent divides the calorie figure by a flat 0.04 kcal per step, a rule of thumb that takes no account of the bodyweight you just entered, even though the calories above it scale with weight directly. It is a rough comparison, not a conversion.
What people use it for
- Comparing the energy cost of different activities
- Estimating a session burn without a wearable
- Understanding why exercise alone moves weight slowly
- Converting a session into a share of daily expenditure
- Checking a cardio machine's calorie readout against the published MET value
- Working out the net cost of a session after subtracting resting burn
- Planning fuelling for a long session
Questions
MET × 3.5 × bodyweight in kg ÷ 200 gives kcal per minute. Multiply by the duration in minutes.
A multiple of resting metabolic rate. One MET is sitting quietly. Walking at a moderate three miles an hour is 3.5 METs, brisk walking at 3.5 mph is 4.3, and running at six miles an hour is 9.8.
Not for everyone. It was set from one 70 kg 40-year-old man. Measured across 769 adults, average resting oxygen use was 2.6 rather than 3.5 ml/kg/min, which means the standard value runs high for a large part of the population.
Wearable energy estimates commonly sit 20 to 30 per cent away from measured expenditure. Neither method is exact, but this one shows its working.
Yes, proportionally, because the equation multiplies by mass. A heavier person moving the same distance does more work. Body composition matters too, and the equation cannot see it.
Generally not in full. The figures are gross, they include the resting burn you would have had anyway, and the underlying constant leans high.
Less than the calorie figure above them. That row uses a flat 0.04 kcal per step for everyone, which ignores the weight the rest of the calculation depends on.
The Compendium of Physical Activities, which assigns a MET value to each activity from the published measurement literature. It has been through four editions — 1993, 2000, 2011 and the 2024 Adult Compendium, which expanded it to 1,114 activities. The figures in the list here are the 2011 ones, each checked against the entry for the activity it names. The revisions are not cosmetic: freestyle laps at an easy pace went from 8.0 in 1993 to 5.8 in 2011.