Calculadora de Calorías Quemadas

This calculator estimates the calories burned during a specific activity using its MET value, a standard measure of exercise intensity. It is designed to give a reasonable working estimate for planning training, nutrition or general activity tracking, not a precise measurement of individual energy expenditure.

La fórmula

Calories burned = MET x weight (kg) x duration (hours)

• MET = the metabolic equivalent value assigned to the activity
• weight = body weight in kilograms
• duration = time spent doing the activity, in hours

MET values are drawn from the Compendium of Physical Activities, first published by Barbara Ainsworth and colleagues in 1993 and periodically updated, most recently a third update in 2024, which catalogues the energy cost of hundreds of activities relative to resting metabolism.

How the calculation works

A MET, or metabolic equivalent of task, is a ratio: it expresses how many times more energy an activity uses compared with sitting quietly at rest, which is defined as 1 MET. Walking at a moderate pace is roughly 3.5 METs, meaning it burns about three and a half times as much energy as resting; running at a fast pace can exceed 10 METs. The Compendium of Physical Activities assigns a MET value to hundreds of specific activities, from housework to competitive sports, based on measured or estimated oxygen consumption.

To estimate calories burned, the MET value is multiplied by body weight in kilograms and by the duration of the activity in hours. This works because energy expenditure scales fairly closely with body mass: a heavier person generally burns more calories doing the same activity for the same amount of time than a lighter person, all else being equal.

How to read your result

The table below gives approximate MET values for common activities, drawn from the Compendium of Physical Activities. Moderate-intensity activity generally falls between about 3 and 6 METs, and vigorous-intensity activity is above about 6 METs, a threshold also used by the CDC when classifying physical activity intensity for public health guidance.

Why the same activity can burn different calories for different people

Because the formula multiplies MET by body weight, two people doing the identical activity for the identical duration will get different calorie estimates if their body weights differ; this is expected and reflects the larger metabolic cost of moving a larger body mass, not a flaw in the calculation. Fitness level also affects real-world energy expenditure in ways the MET table cannot capture: a highly trained athlete may move more efficiently and burn somewhat fewer calories at a given pace than an untrained person working at the same MET-equivalent effort.

MET-based estimates are widely used in public health research precisely because they standardise activity intensity across studies and populations, which is useful for comparing activities and setting general activity goals, such as the CDC and WHO recommendation of at least 150 minutes a week of moderate-intensity aerobic activity. For precise individual calorie tracking, wearable devices using heart rate or motion sensors, or laboratory measurement of oxygen consumption, are more accurate than a MET table lookup.

METs beyond exercise planning: functional capacity and daily tasks

MET values are also used clinically, most notably to describe functional capacity during cardiac risk assessment. A patient who can sustain at least 4 METs of exertion, roughly equivalent to climbing a flight of stairs or walking briskly, without symptoms is generally considered to have adequate reserve for many types of surgery and daily activity, a threshold referenced in perioperative cardiac risk guidance from the American College of Cardiology and American Heart Association. This is a different use of the same MET concept: rather than estimating calories, it estimates how much exertion a person's heart and lungs can tolerate.

The table below extends the activity list to everyday tasks and higher-intensity options not covered above, useful for estimating calorie burn outside structured workouts, such as housework, yard work or an active job.

• A sustained MET of 4 or above without symptoms is a common clinical benchmark for adequate functional capacity before many surgical procedures.
• Daily non-exercise tasks add up: a couple of hours of moderate-intensity housework or gardening can burn a similar number of calories to a structured 30-minute workout.
• Stair climbing spans an unusually wide MET range, from a gentle 4 METs on a slow ascent to nearly 9 METs when climbing quickly, depending entirely on pace.

Limitaciones

• MET values are averages measured across groups of people and do not account for individual differences in fitness, technique, body composition or fat-to-muscle ratio.
• The formula does not adjust for age or sex, both of which influence real energy expenditure independent of the MET value assigned to an activity.
• MET-based estimates have not been validated for children, and separate compendiums exist specifically for youth activity.
• Activities performed at unusual intensity, incline, load or environmental temperature compared with the Compendium's reference conditions can have meaningfully different true energy costs than the tabulated MET value suggests.
• This method is not appropriate for people with conditions that markedly alter metabolic response to exercise, such as some cardiac or metabolic conditions, without individualised medical guidance.

Preguntas frecuentes

What is a MET exactly?

A MET, metabolic equivalent of task, is a ratio of an activity's energy cost to the energy cost of sitting quietly at rest. One MET is the resting rate; an activity rated at 5 METs uses about five times as much energy as resting.

How accurate are MET-based calorie estimates?

They give a reasonable population-level estimate but can be off by a meaningful margin for any individual, since they do not account for personal fitness, technique or exact effort level. They are best used for general planning rather than precise calorie tracking.

Why does the calculator ask for my body weight?

Because energy expenditure during an activity is closely related to body mass, heavier bodies generally burn more calories doing the same activity for the same time. The formula multiplies the activity's MET value by body weight to reflect this.

Where do MET values come from?

They come from the Compendium of Physical Activities, a research reference first published in 1993 and updated periodically by exercise scientists, which lists measured or estimated MET values for hundreds of everyday and sporting activities.

Do daily chores like cleaning or gardening really count as exercise?

Yes. Housework and yard work carry real MET values, often in the moderate-intensity range of 3 to 5.5, and public health guidelines such as those from the CDC count this kind of activity toward the recommended 150 minutes a week of moderate-intensity movement.

What does it mean when a doctor asks if I can manage "4 METs of activity"?

It refers to functional capacity, a clinical shorthand for whether a person can climb a flight of stairs or walk briskly without chest pain, breathlessness or other symptoms. It is used, among other things, to help assess surgical and cardiac risk before an operation, separately from calorie estimation.

Referencias

1. Herrmann SD, et al. A brief history of the Compendium of Physical Activities. PMC.
2. Centers for Disease Control and Prevention. How to Measure Physical Activity Intensity.
3. Centers for Disease Control and Prevention. What Counts as Physical Activity for Adults.
4. Centers for Disease Control and Prevention. Adult Activity: An Overview.