Calories Burned Calculator
Enter your weight, choose an activity, and set the duration. The calculator uses MET values — the same method exercise physiologists use — to estimate how many calories you burned.
Activity Data
MET Intensity Log
Select your activity and duration to see energy expenditure estimate.
How to read your results
The number you see is a solid baseline — here's what it accounts for and what it doesn't.
Calories burned (in session)
This is your active calorie burn for the duration you entered — the energy your body used to perform the movement, above and beyond resting.
MET value
A multiplier that reflects how much harder an activity is than sitting still. Running at 6 mph has a MET of ~9.8, meaning it burns ~9.8× more energy per minute than rest.
Weight's role
Heavier people burn more calories doing the same activity because more energy is needed to move a larger mass. The formula scales your result directly to your body weight.
What's not included
Post-workout calorie burn (EPOC), calories from digestion, and baseline metabolic rate are not in this number. Your total daily expenditure will be higher.
What is a MET value?
MET stands for Metabolic Equivalent of Task. The concept is straightforward: 1 MET is the energy your body uses at complete rest — roughly 3.5 ml of oxygen per kilogram of body weight per minute. Every activity gets assigned a MET value based on how much harder it is than resting.
A slow walk might be 2.5 METs. Casual cycling is around 6. Running at a hard pace pushes past 10. To estimate calories, the formula multiplies MET × your weight in kg × duration in hours. That's the same math used in research studies, clinical settings, and most serious fitness applications.
MET values for this calculator come from the Compendium of Physical Activities, a database maintained by exercise scientists and updated regularly. It's the most widely cited MET reference in the field.
The formula
Calories = MET × weight (kg) × duration (hours)
Example: 60 kg person, 45 min run at MET 9.8 → 9.8 × 60 × 0.75 = 441 kcal
Activity intensity at a glance
These are the MET values the calculator uses internally. If your specific workout isn't listed, pick the closest match.
| Activity | MET value | Intensity | Kcal / 30 min (70 kg) |
|---|---|---|---|
| Yoga (Hatha) | 2.5 | Light | 88 kcal |
| Walking (3.5 mph) | 4.3 | Moderate | 151 kcal |
| Cycling (leisure) | 6.0 | Moderate | 210 kcal |
| Swimming (laps, moderate) | 8.0 | Vigorous | 280 kcal |
| Running (6 mph) | 9.8 | Vigorous | 343 kcal |
| HIIT | ~10.0 | Very vigorous | 350 kcal |
| Cycling (>20 mph) | 15.8 | Elite | 553 kcal |
Who uses a calorie burn calculator
The tool is simple, but the reasons people reach for it vary quite a bit.
People tracking a calorie deficit
If you're trying to lose weight by eating less than you burn, you need a realistic sense of your exercise output. MET estimates are far more accurate than the inflated numbers on most gym machines, which don't account for your actual weight.
Athletes calculating refueling needs
After a long run or hard training session, knowing your approximate calorie expenditure helps you eat back the right amount — enough to recover without accidentally eating in surplus.
Personal trainers and coaches
A quick MET calculation helps coaches design realistic workout plans and set sensible weekly calorie-burn targets for clients without needing lab equipment.
People managing a health condition
Conditions like type 2 diabetes require careful attention to the relationship between exercise, food intake, and blood sugar. A calorie-burn estimate gives useful context, though always in combination with medical guidance.
Curious exercisers
Sometimes you just want to know whether that 20-minute walk actually did anything, or whether the spin class burned more than your usual run. The answer is usually more nuanced than you'd expect.
The afterburn effect (EPOC)
EPOC stands for Excess Post-exercise Oxygen Consumption. After intense exercise, your body keeps burning calories at an elevated rate while it restores oxygen levels, clears metabolic byproducts, and repairs muscle tissue. This happens whether you feel it or not.
For low-to-moderate intensity exercise (walking, gentle cycling), EPOC is negligible — maybe 5% on top of in-session burn. For high-intensity work like sprinting, heavy lifting, or HIIT, it can add 6–15% more calories burned over the next 12–24 hours.
This calculator shows your in-session calorie burn only. If you do intense workouts regularly, your actual daily energy expenditure will be meaningfully higher than the number on screen.
+~5%
Low intensity (walking)
+~8%
Moderate (steady run)
+6–15%
High intensity (HIIT)
A worked example
So you can see exactly what the calculator is doing with your numbers.
Person: 75 kg | Activity: Running at 6 mph (MET 9.8) | Duration: 40 minutes
Note: The calculator shows 490 kcal (in-session). The EPOC adjustment is an estimate you apply separately based on your workout intensity.
Known limitations
- —MET values are population averages. Fitter people tend to burn slightly fewer calories for the same activity because their bodies are more efficient at it.
- —The formula doesn't account for age, sex, or body composition. Muscle burns more energy than fat, so two people with the same weight can have different calorie burns.
- —Effort intensity matters. A "run" in the activity list assumes a specific pace. If you ran faster or slower, the actual MET will differ from the listed value.
- —This calculator doesn't include your basal metabolic rate (BMR) — the calories you burn just staying alive. For total daily expenditure, you'd need to add BMR on top.
- —Not a medical tool. If you're managing a condition like diabetes or heart disease, calorie estimates should supplement, not replace, clinical guidance.
Frequently asked questions
What is a MET value and where do your numbers come from?
MET (Metabolic Equivalent of Task) is a ratio of active energy use to resting energy use. The MET values in this calculator come from the Compendium of Physical Activities — the standard academic reference in exercise science, compiled by researchers at Arizona State University.
How close is this to what a fitness tracker shows?
Most consumer fitness trackers (Fitbit, Garmin, Apple Watch) use heart rate combined with a proprietary algorithm. MET-based calculations and heart-rate-based calculations typically agree within 10–20% for most people. Neither is perfectly accurate — they're both estimates.
Do I burn fewer calories as I get fitter?
Broadly yes, for the same activity at the same intensity. A trained runner is more mechanically efficient than a beginner, so they use slightly less oxygen — and burn slightly fewer calories — per mile. This is one reason why progressively increasing workout intensity matters.
Should I eat back the calories this calculator shows?
Not necessarily all of them. If you're trying to lose weight, eating back 50–75% of exercise calories is a common approach that accounts for both calculator error and the risk of overestimating burn. Always prioritise hunger cues and energy levels over hitting a specific number.
Why does the gym treadmill show a much higher number?
Gym machines are notoriously bad at calorie estimation. Many don't use your weight, and those that do often use flattering default assumptions. MET-based estimates tied to your actual weight are generally more conservative and more accurate.