How many calories you actually burn
Find out in seconds how many calories you burn with exercise. Pick the activity (walking, running, cycling, swimming, weights, HIIT…), enter your weight and the minutes, and we compute the burn with the MET model, the scientific standard for estimating each activity’s energy use.
Estimate using the MET model (metabolic equivalents). Real burn varies with intensity, fitness and efficiency. Guidance only.
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How are calories burned calculated?
The calculation uses METs (metabolic equivalents), the standard way exercise physiology quantifies effort: 1 MET is what you burn sitting still, and every activity gets a multiplier from the Compendium of Physical Activities. Calories burned = METs x weight in kg x hours. That is why a heavier person burns more for the same walk — moving more mass costs more energy. Two honest caveats. First, the figure is gross, not net: part of it you would have burned anyway just being alive. Second, intensity within an activity varies enormously, so treat the result as an order of magnitude rather than a precise count.
Calories burned by activity and body weight
Half an hour of each, at two different body weights. The part almost nobody says out loud: 10,000 steps is about 60-70 minutes of walking, so roughly 250 kcal at 70 kg — well below what any tracker promises, and less than one pastry. Exercise amplifies a deficit; it is not the engine.
| Activity (30 min) | MET | 70 kg | 95 kg |
|---|---|---|---|
| Walking, easy | 3.5 | 184 | 245 |
| Walking, brisk | 5.0 | 263 | 350 |
| Running at 9-10 km/h | 9.8 | 515 | 686 |
| Cycling, moderate | 7.5 | 394 | 525 |
| Swimming, light | 5.8 | 305 | 406 |
| Weights, vigorous | 5.0 | 263 | 350 |
| Yoga, gentle | 2.5 | 131 | 175 |
| House cleaning | 3.3 | 173 | 231 |
Computed as MET x weight in kg x hours, using MET values from the Compendium of Physical Activities (Ainsworth et al.). These are reference ranges for healthy adults, not a diagnosis or individual advice.
FAQ
How many calories does 30 minutes of walking burn?
At a brisk pace (around 5 km/h, roughly 3.5 METs), a 70 kg person burns about 120-130 kcal in half an hour. At a stroll it is closer to 80. Weight and pace move the figure far more than any app's tracking precision does.
How many calories does running burn?
Running is roughly 8-12 METs depending on pace. A 70 kg person at a moderate pace burns about 550-650 kcal an hour. A useful rule of thumb: running burns roughly 1 kcal per kilo per kilometre, largely independent of how fast you cover it.
Should I eat back the calories I burn?
Partially, and carefully. Wearables tend to overestimate exercise burn — sometimes by a lot — so eating back the full figure is the most common way a deficit quietly disappears. A common approach is to eat back about half, and adjust from what the scale does over a few weeks.
Do watches and fitness bands measure calories well?
They are decent for heart rate and steps, and poor for calories: validation studies routinely find errors of 20-30% or more, almost always upwards. Use them to compare your own sessions week to week, not as an absolute number to eat against.