A calories burned calculator estimates exercise energy as MET value × body weight (kg) × time (hours). A 150 lb (68 kg) person burns about 333 kcal gross in 30 minutes of running at 6 mph (9.8 METs) and about 146 kcal walking briskly. Net calories, which subtract the energy you would burn resting anyway, are lower: about 299 and 112 kcal.
Key takeaways
- Calories burned = MET × weight in kg × hours; the MET value comes from the Compendium of Physical Activities.
- Gross calories include your resting burn during the activity; net calories subtract 1 MET and are the better figure for comparison with a calorie target.
- Wrist-worn fitness trackers showed large errors in estimating energy expenditure in a 2017 laboratory study, so treat them as rough guides.
- If your TDEE activity level already counts your workouts, do not add exercise calories back on top of your target.
How this calories burned calculator works
Choose an activity from the list, enter the duration in minutes and your weight. The calculator looks up the activity’s MET value, then returns gross calories, net calories, the MET value itself and calories per minute. A small table shows 30 minutes of eight popular activities at your weight, so you can compare them.
The activity list uses MET values from the Compendium of Physical Activities (Ainsworth et al., 2011; Herrmann et al., 2024). The estimates are for adults and assume an average person at a steady effort.
How are calories burned calculated with METs?
Gross kcal = MET × weight (kg) × hours Net kcal = (MET − 1) × weight (kg) × hours
One MET is the resting rate, roughly 1 kcal per kg per hour. The Compendium assigns each activity a multiple of that rate. Brisk walking at 3.5 mph is 4.3 METs, running at 6 mph is 9.8 and hatha yoga is 2.5.
What is the difference between gross and net calories?
Gross calories are the total energy you burn during the activity. Net calories are the extra energy beyond what you would have burned sitting still for that time. If you are comparing exercise with a calorie target, net is closer to the number that matters, because your resting burn is already inside your BMR and TDEE.
For vigorous exercise the gap is small: at 9.8 METs, net is about 90% of gross. For gentle activity it is large: at 2.5 METs (yoga), net is only 60% of gross.
How many calories does 30 minutes of exercise burn?
| Activity (30 minutes) | METs | 150 lb: gross / net | 200 lb: gross / net |
|---|---|---|---|
| Yoga, hatha | 2.5 | 85 / 51 kcal | 113 / 68 kcal |
| Walking, brisk (3.5 mph) | 4.3 | 146 / 112 kcal | 195 / 150 kcal |
| Elliptical, moderate | 5.0 | 170 / 136 kcal | 227 / 181 kcal |
| Swimming laps, light/moderate | 5.8 | 197 / 163 kcal | 263 / 218 kcal |
| Weight training, vigorous | 6.0 | 204 / 170 kcal | 272 / 227 kcal |
| Hiking | 6.0 | 204 / 170 kcal | 272 / 227 kcal |
| Dancing, aerobic | 7.3 | 248 / 214 kcal | 331 / 286 kcal |
| Cycling, 12–13.9 mph | 8.0 | 272 / 238 kcal | 363 / 318 kcal |
| Circuit training / HIIT | 8.0 | 272 / 238 kcal | 363 / 318 kcal |
| Running, 6 mph | 9.8 | 333 / 299 kcal | 445 / 399 kcal |
The 200 lb person burns about a third more than the 150 lb person for the same work, because the formula scales directly with body weight. Walking is covered in more depth in the steps to calories calculator.
Why do fitness trackers overestimate calories burned?
Trackers estimate energy from heart rate, movement and the profile you enter. In a laboratory comparison of seven wrist-worn devices, heart-rate readings were comparatively accurate, but the energy expenditure estimates showed large errors (Shcherbina et al., 2017).
That is why one device’s “800 calories” is a poor number to plan around. Use trackers to compare your own sessions over time, not to decide how much extra to eat. Equations like this calculator’s are also approximate, but they are at least transparent and consistent.
Should I eat back exercise calories?
Probably not all of them. Your TDEE is built from your BMR times an activity factor, and that factor is meant to cover your typical weekly exercise. If you chose “moderate” because you train 3–5 days a week, adding the calories from each workout on top counts them twice, and the usual result is a deficit that quietly disappears.
Two cleaner approaches work:
- Set a fixed target and ignore workouts. Choose your activity level honestly, set your calories with the calorie deficit calculator, and stay consistent.
- Pick a lower activity level and eat back net calories. Choose “sedentary” or “light”, then add a conservative share, for example half, of the net calories you log. Check the result against your scale trend.
Whichever you choose, your real weight trend settles the question. The adaptive TDEE calculator measures what your body is actually using, workouts included.
What affects how many calories you burn exercising?
- Body weight. Heavier bodies move more mass, so the same activity costs more.
- Intensity. METs rise steeply with speed: 5 mph running is 8.3 METs, 8 mph is 11.8.
- Efficiency and technique. Experienced swimmers and runners often use less energy at a given pace than beginners.
- Terrain, wind and load. The standard MET values are averages and can’t capture hills or headwinds.
For the bigger picture of how exercise fits into daily energy use, see what is TDEE and the guide to TDEE accuracy.
Frequently asked questions
How many calories does 30 minutes of exercise burn?
It depends on the activity and your weight. For a 150 lb person, 30 minutes of yoga burns about 85 kcal gross, brisk walking about 146, cycling at a moderate pace about 272 and running at 6 mph about 333. A 200 lb person burns about a third more.
What is a MET?
A MET (metabolic equivalent of task) is a multiple of your resting energy use. One MET is the energy you use sitting quietly, about 1 kcal per kg of body weight per hour. Running at 6 mph is about 9.8 METs, so it uses roughly 9.8 times resting energy.
Should I eat back the calories I burn exercising?
Usually not all of them. If your activity level already reflects your regular workouts, they are in your TDEE, and eating them back counts them twice. If you do an unusual extra session, eating back part, say half, of the net calories is a cautious option.
How accurate are calorie counters on cardio machines and watches?
Not very. Machines usually don't account for your body, and wrist-worn trackers showed large energy-expenditure errors in laboratory testing. Use any device number as a trend across similar workouts, and check it against your actual weight trend.
Why do I burn fewer calories than my friend doing the same workout?
Body weight is the main driver: heavier people burn more per minute. Fitness, efficiency, intensity and technique also matter. Two people doing the same workout can burn quite different amounts, which is why a formula based on your own weight beats a generic number.
References
- Ainsworth BE, Haskell WL, Herrmann SD, et al. (2011). 2011 Compendium of Physical Activities: a second update of codes and MET values. Medicine & Science in Sports & Exercise 43(8):1575–1581.
- Herrmann SD, Willis EA, Ainsworth BE, et al. (2024). 2024 Adult Compendium of Physical Activities: a third update of the energy costs of human activities. Journal of Sport and Health Science 13(1):6–12.
- Shcherbina A, Mattsson CM, Waggott D, et al. (2017). Accuracy in wrist-worn, sensor-based measurements of heart rate and energy expenditure in a diverse cohort. Journal of Personalized Medicine 7(2):3.
- Mifflin MD, St Jeor ST, Hill LA, Scott BJ, Daugherty SA, Koh YO (1990). A new predictive equation for resting energy expenditure in healthy individuals. American Journal of Clinical Nutrition 51(2):241–247.