Calories Burned by Activity

The calories burned calculator estimates how many calories an activity uses based on three inputs: the activity, your body weight, and the time you spend doing it. It covers walking, running, cycling, swimming, gym work, and common daily tasks, and returns an energy expenditure figure in calories for the session. The estimate comes from the MET system, the standard method researchers use to compare the energy cost of different activities.

Calories matter to people for different reasons: weight management, training load, meal planning, or simple curiosity about how a workout compares to a slice of cake. The number this tool produces is an estimate, not a measurement. The MET system is a population average built from laboratory studies, and any individual burns more or less than the average depending on their body, their fitness, and how hard they actually push.

What a MET is

MET stands for metabolic equivalent of task. One MET is the rate of energy use while sitting quietly, and it is set at about 1 kilocalorie per kilogram of body weight per hour for an average adult. Every activity has a MET value that describes how many times harder it is than sitting still.

• Sitting quietly: about 1.0 MET
• Walking at a moderate pace: about 3.5 MET
• Jogging: about 7.0 MET
• Running at a solid pace: about 9.8 MET
• Vigorous cycling: about 8.0 to 10 MET
• Moderate swimming: about 6 MET

A MET value of 8 means the activity uses eight times the energy of sitting. The values come from the Compendium of Physical Activities, a research database maintained by exercise scientists that assigns standard MET values to hundreds of activities. The compendium is the common reference behind fitness trackers, gym equipment, and research papers, so a number from this calculator will be in the same ballpark as the one on a treadmill display.

The MET scale describes the intensity of the activity itself, not the person doing it. A heavier person burns more calories at the same MET value because moving a heavier body takes more energy, which is why body weight is the second input.

The formula

The standard estimation formula multiplies three factors together:

calories per minute = MET × 3.5 × weight in kg ÷ 200

The 3.5 represents the average oxygen consumption of a resting adult, about 3.5 millilitres of oxygen per kilogram per minute, and the 200 converts the oxygen-based energy expression into calories. The full formula then multiplies by the minutes spent:

calories = MET × 3.5 × weight in kg ÷ 200 × minutes

For a 70 kg person doing an activity at 5 MET for 30 minutes:

5 × 3.5 × 70 ÷ 200 × 30 = 183.75 calories

For a 90 kg person doing the same activity for the same time:

5 × 3.5 × 90 ÷ 200 × 30 = 236.25 calories

The weight term does the work: the 90 kg person burns about 29% more than the 70 kg person at the same intensity and duration. This is why the same run burns different calories for different people, and why weight is a required input rather than an optional detail.

How to use the tool

1. Enter your body weight in kilograms, or in pounds if you prefer. The tool converts pounds to kilograms internally.
2. Pick the activity that matches what you did. The closer the match, the better the estimate. Walking at a brisk pace and walking while pushing a pram are different MET values.
3. Enter the duration in minutes. Use the time actually spent moving, not the time you spent at the gym including rests between sets.
4. Read the estimated calories burned. The tool also shows the per-minute rate, which is useful for comparing activities.

The order of the inputs does not affect the result. The formula is linear in all three factors: double the weight, double the calories; double the time, double the calories; double the MET, double the calories. That linearity is what makes the calculator useful for quick what-if comparisons, such as whether an extra 10 minutes of walking covers the snack you are considering.

Example activities and their MET values

These are representative values from the compendium. The tool's activity list uses the same sources, and where an activity is not listed, the closest match is a reasonable basis for an estimate.

Worked examples

Example 1: a 70 kg person walking briskly for 45 minutes.

Brisk walking at 4.3 MET: 4.3 × 3.5 × 70 ÷ 200 = 5.27 calories per minute. Over 45 minutes: 5.27 × 45 = 237 calories. A moderate walk like this is a small but real contribution to daily energy balance.

Example 2: a 75 kg person running at 10 km/h for 30 minutes.

Running at 9.8 MET: 9.8 × 3.5 × 75 ÷ 200 = 12.86 calories per minute. Over 30 minutes: 12.86 × 30 = 386 calories. The same person walking the same 30 minutes at 3.5 MET burns about 138 calories, so running at this pace uses nearly three times the energy of moderate walking per minute.

Example 3: a 60 kg person swimming moderately for 40 minutes.

Moderate swimming at 6.0 MET: 6.0 × 3.5 × 60 ÷ 200 = 6.3 calories per minute. Over 40 minutes: 6.3 × 40 = 252 calories. Swimming's appeal is that the whole body works and the intensity is easy to hold, even though the per-minute burn is modest at moderate effort.

Example 4: the weight effect on the same workout.

Two people do the same 30-minute session at 7 MET. A 65 kg person burns 7 × 3.5 × 65 ÷ 200 × 30 = 238.9 calories. An 85 kg person burns 7 × 3.5 × 85 ÷ 200 × 30 = 312.4 calories. Same workout, 74 calories apart, purely from body weight.

Example 5: daily tasks add up.

A 70 kg person does 20 minutes of housework at 3.3 MET: 3.3 × 3.5 × 70 ÷ 200 × 20 = 80.9 calories. Small by itself, but an hour a day of such tasks over a week is roughly 560 calories, which is not nothing for someone whose goal is a modest daily deficit.

Accuracy and its limits

The MET estimate has real limitations, and knowing them keeps the number in perspective.

The compendium values are averages. Actual intensity varies within an activity: a gentle jog and a hard run both count as "running" but burn very differently. The tool uses the standard value for each activity, so your personal figure can be 20% to 40% higher or lower depending on how hard you work relative to the reference.

Body composition matters. The formula uses total weight, but muscle tissue burns more energy than fat tissue at rest and during exercise. Two people at the same weight can burn different calories in the same workout if their muscle mass differs. The formula cannot see body composition, so it is an average-based estimate.

Fitness changes the cost. A trained person performs the same activity more efficiently and burns slightly less than an untrained person at the same pace, a gap that widens as fitness improves. This is the opposite of the common intuition, but it is why elite runners do not burn proportionally more than recreational runners for the same distance.

The oxygen conversion assumes average respiratory exchange. The 3.5 millilitres per kilogram per minute resting baseline and the 5 kcal per litre of oxygen conversion are population conventions, accurate for most people but not for everyone. For clinical or research-grade precision, indirect calorimetry measures actual oxygen use; no consumer calculator does this.

None of this makes the estimate useless. For tracking trends, planning meals, and comparing activities, the MET method is consistent and well validated. It is the same method used in published physical activity research. Treat the result as a planning figure, not a billing statement.

Frequently Asked Questions

How many calories do I burn walking for 30 minutes?

At a moderate pace of about 5 km/h, walking is roughly 3.5 MET. A 70 kg person burns 3.5 × 3.5 × 70 ÷ 200 × 30 = 129 calories. The exact figure scales with your weight and pace.

How many calories does running burn per minute?

Running at about 10 km/h is roughly 9.8 MET. A 70 kg person burns about 12 calories per minute, so 360 calories in 30 minutes. Heavier runners burn more per minute at the same pace.

What is a MET?

A metabolic equivalent of task, the ratio of the energy an activity uses to the energy of sitting quietly. One MET is about 1 kilocalorie per kilogram of body weight per hour. An activity at 8 MET uses eight times the energy of sitting.

Why do I burn fewer calories than the treadmill says?

Treadmills and fitness trackers use their own estimates, often without your weight or with a generous default. The MET formula with your actual weight is usually the more conservative figure. Machines also assume a steady intensity you may not hold.

Does muscle mass affect calories burned?

Yes. Muscle burns more energy than fat at rest and during exercise, so two people at the same weight can burn different calories in the same workout. The MET formula uses total weight only and cannot see body composition.

Are calories burned the same for everyone doing the same activity?

No. Weight, muscle mass, fitness, and actual intensity all change the number. The MET value is a population average, so your personal burn can be 20% to 40% either side of the estimate.

How accurate is this calculator?

It uses the standard MET method from the Compendium of Physical Activities, the same approach used in exercise research. As an estimate it is consistent and useful for planning and comparison, but it is not a laboratory measurement of your actual energy use.

Can I use this to plan weight loss?

As a planning aid, yes. A common approach is a daily deficit of 300 to 500 calories, achieved through a combination of diet and activity. The tool shows the activity side of that ledger, but food intake is the larger and more controllable side for most people.

References

• Ainsworth BE, Haskell WL, et al., Compendium of Physical Activities: a second update of codes and MET values, Medicine & Science in Sports & Exercise, 2011.
• American College of Sports Medicine, ACSM's Guidelines for Exercise Testing and Prescription, for the MET-based energy expenditure formula.
• World Health Organization publications on physical activity and energy expenditure.

Q: Can the Calories Burned Calculator: Activity and MET be used for professional or commercial purposes? A: Yes, the Calories Burned Calculator: Activity and MET provides mathematically correct results that are suitable for professional, commercial, and educational use. For the Calories Burned Calculator: Activity and MET, For the Calories Burned Calculator: Activity and MET, For high-stakes applications (medical, legal, financial), verify results with a domain expert. For the Calories Burned Calculator: Activity and MET, the Calories Burned Calculator: Activity and MET formulas used are well-established and validated against reference standards.

Q: How often are the Calories Burned Calculator: Activity and MET formulas updated? A: the Calories Burned Calculator: Activity and MET formulas are based on established scientific, mathematical, or industry-standard references and rarely require updates. When standards change (e.g., new physical constants, revised tax brackets, updated standards), the Calories Burned Calculator: Activity and MET is updated to reflect the current authoritative source. For the Calories Burned Calculator: Activity and MET, For the Calories Burned Calculator: Activity and MET, Each calculator's references section lists the specific sources used.