Health Guide
How Calories Burned Is Calculated
One formula, one table of MET values, and your body weight. How exercise calorie estimates actually work.
Last updated: August 29, 2026
Exercise calorie estimates come from a surprisingly simple formula and a published table of activity intensities. Knowing both makes it much clearer what the number can and cannot tell you.
The formula
kcal = MET × weight(kg) × duration(hours)That is the entire calculation. Three inputs: how intense the activity is, how heavy you are, and how long you did it for.
Our Calories Burned Calculator applies it across a curated set of activities.
What a MET is
A MET (metabolic equivalent of task) expresses an activity's energy cost relative to sitting at rest. One MET is roughly your resting metabolic rate. An activity rated at 8 METs costs about eight times as much energy per minute as sitting still.
The values come from the 2011 Compendium of Physical Activities (Ainsworth, Haskell, Herrmann and colleagues), published in Medicine & Science in Sports & Exercise. It is the standard reference for this kind of estimate.
The activities and their intensities
| Activity | MET | 30 min at 70 kg |
|---|---|---|
| Yoga (Hatha) | 2.5 | 88 kcal |
| Housework (general) | 3.3 | 116 kcal |
| Walking (brisk, ~3.5 mph) | 4.3 | 150 kcal |
| Swimming (freestyle, moderate) | 5.8 | 203 kcal |
| Strength training (vigorous) | 6.0 | 210 kcal |
| Cycling (moderate, 12–14 mph) | 8.0 | 280 kcal |
| Running (~6 mph) | 9.8 | 343 kcal |
| Rope skipping (moderate) | 11.8 | 413 kcal |
The spread is instructive: half an hour of rope skipping costs nearly five times what half an hour of yoga does.
A worked example
Running (MET 9.8) for 30 minutes at 70 kg:
9.8 × 70 × 0.5 = 343 kcalNote that duration goes in as hours, so 30 minutes is 0.5. And note that weight appears directly — a heavier person burns more doing the identical activity, because moving more mass costs more energy.
Why the number is a ballpark
MET values are population averages. They describe the typical energy cost of an activity across many people, at a typical intensity. Your actual burn depends on things the table cannot see:
- Effort within the activity. "Cycling (moderate)" covers a wide range of real efforts.
- Fitness. A trained person is often more efficient, sometimes burning less for the same output.
- Body composition. Weight is in the formula; what that weight is made of is not.
- Terrain, conditions, and technique.
This is why we label the calculator moderate confidence and why how accurate are calorie burn estimates is worth reading before you eat back what a session "earned".
Don't double-count it
An important interaction: if you already calculated your TDEE, your activity multiplier already includes your usual training. Adding a calories-burned figure on top counts the same exercise twice.
Use this calculator to compare activities or to account for something outside your normal routine — not to inflate a TDEE that already accounts for it. Choosing your activity level honestly covers that trap in more detail.
The bottom line
Multiply the activity's MET value by your weight in kilograms and the duration in hours. The MET values come from a published compendium and are population averages, so treat the result as a ballpark for comparison rather than a precise count. Run yours on the Calories Burned Calculator.
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