Calculate calories burned for 40+ activities including walking, running, cycling, swimming, and strength training. Based on MET (Metabolic Equivalent of Task) values from the Compendium of Physical Activities — the same scientific source used by fitness researchers. Enter your weight, activity, and duration. Free, instant, no sign-up.
40+ activities using MET values — walking, running, gym & more
Calorie burn during exercise is calculated using MET values (Metabolic Equivalents of Task) from the Compendium of Physical Activities — the gold-standard reference database compiled from exercise science research. The formula: Calories/minute = MET × weight in kg × 0.0175. A 160 lb (73 kg) person running at 6 mph (MET = 9.8) burns 12.5 calories per minute — 375 calories in 30 minutes. Walking at 3.5 mph (MET = 3.8) burns 4.8 cal/min — 144 calories in 30 minutes. Vigorous weightlifting (MET = 6.0) burns 7.7 cal/min — 231 calories in 30 minutes. These are gross calorie burns (total including BMR) — net calories burned from exercise are approximately 75–85% of these numbers.
Weight loss through exercise alone is often overestimated. Running for 30 minutes burns ~375 calories, but the body partially compensates by reducing non-exercise activity (NEAT — fidgeting, posture, etc.) by 100–200 calories. The net deficit from one 30-minute run might be only 175–250 calories. This is why dietary calorie control is more efficient than exercise alone for weight loss, and why fitness experts say "you can't out-exercise a bad diet." Exercise's true value for weight management is in maintaining metabolic rate and muscle mass, improving insulin sensitivity, and making sustainable caloric restriction more effective.
Covering the same distance burns similar calories regardless of speed — but running does it faster. Walking 3 miles at 3 mph (60 min): ~250 cal. Running 3 miles at 6 mph (30 min): ~375 cal. The running bonus comes from elevated post-exercise oxygen consumption (EPOC) — your metabolism stays elevated 30–90 minutes after vigorous exercise, burning an additional 50–150 calories.
Weight training burns fewer calories per session than cardio (200–400 cal/hr vs 400–800 cal/hr for running), but builds muscle that raises your BMR permanently. Every pound of muscle burns ~6 cal/day at rest. Adding 10 lbs of muscle raises your BMR by ~60 cal/day — 21,900 extra calories burned per year without additional exercise. This is why strength training is the #1 long-term metabolism booster.
Swimming burns 500–700 calories per hour for vigorous freestyle — comparable to running but with near-zero joint stress, making it ideal for injury recovery or high-BMI individuals. Water's density means your muscles work harder than on land. Breaststroke burns slightly fewer calories than freestyle; butterfly stroke burns the most (~800 cal/hr at vigorous pace).
Outdoor cycling at 14–16 mph: ~560 cal/hr. Stationary bike moderate: ~400 cal/hr. Peloton/spin class vigorous: 500–700 cal/hr. Cycling's calorie burn advantage: you can maintain higher effort for longer durations due to lower perceived exertion vs running. NEAT (non-exercise activity) suppression is also lower after cycling than after running for most people.
Energy cost of activity is estimated using metabolic equivalents. One MET is the oxygen consumption of sitting quietly, standardised at 3.5 millilitres of oxygen per kilogram of body weight per minute; every activity is then catalogued as a multiple of that resting rate. The Compendium of Physical Activities, maintained since 1993, assigns MET values to hundreds of activities, and the formula converts oxygen consumption into calories. Two caveats: the MET value already includes your resting metabolism, so the figure is gross rather than net expenditure, and published values are population averages that take no account of fitness or efficiency — a trained runner burns measurably less at the same speed than an untrained one.
Calories = MET × 3.5 × weight(kg) ÷ 200 × minutesNet calories = Gross − (resting rate × minutes)Walking 3.5 · Cycling 8.0 · Running 10 km/h 9.8 · Swimming 7.0where:
Assumptions: Population averages. Fitness, terrain, temperature and technique all move the real figure, and wearable estimates of the same session routinely differ by 20% or more from these values and from each other.
The 10 km run from the pace example above, costed in calories.
Result738 calories gross — about 674 net of resting metabolism
The gross-versus-net distinction matters when you eat back exercise calories: using 738 rather than 674 quietly adds 64 calories to the day. Over a week of daily runs that is most of a pound a year, which is how small accounting errors defeat otherwise sound plans.