Calories Burned Calculator — Precision Activity Tracking
If you're trying to nail down a calorie deficit or just figure out what you actually burned on your run, generic "calories burned per hour" charts aren't going to cut it. A 130lb woman and a 200lb man don't burn the same energy doing the exact same workout.
This calculator does the math the long way. It finds your Basal Metabolic Rate (BMR) first, then applies scientific Metabolic Equivalent of Task (MET) multipliers to figure out your exact burn. You can stack multiple activities together above to map out your whole session.
Reviewed by: Saim S., independent health & fitness tool developer
Methodology: Mifflin-St Jeor equation (Mifflin et al., 1990) & Compendium of Physical Activities (Ainsworth et al.)
Last Updated: April 2026
Privacy: All calculations run in your browser. No data is stored or transmitted.
Why Tracking Calories Burned Matters
Whether you're trying to lose fat, build muscle, or just not crash during a marathon, it helps to know what's actually going out of the tank. Your total daily burn comes down to three things: keeping your organs running, digesting your food, and moving your body.
Getting a real grip on what you burn during workouts (and just walking around) lets you:
- Pace your weight loss: Hit a safe deficit without starving yourself.
- Fuel up properly: Put back what you burned on heavy training days so you don't stall out.
- Hold steady: Find your actual maintenance numbers.
If you overestimate your burn, you wipe out your deficit. If you underestimate it, your workouts suffer.
How We Calculate Calories Burned (The BMR + MET Method)
Most simple calculators use a formula based entirely on weight: Calories = Weight(kg) × MET × Hours. While okay for a rough guess, it ignores the fact that a 30-year-old male burns calories at a different baseline rate than a 60-year-old female, even if they weigh the same.
We do it the slightly harder way:
Step 1: Find Your BMR
We use the Mifflin-St Jeor equation to find out what you burn at complete rest:
For Men: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) + 5
For Women: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) − 161Step 2: Apply the MET Multiplier
Once we know your hourly resting burn, we multiply it by how hard the task is.
Calories Burned = (BMR / 24) × MET Value × (Duration in Minutes / 60)This grounds the final number in your actual physiology.
Understanding MET Values
MET stands for Metabolic Equivalent of Task. It's just a scientific multiplier used to compare the effort of an activity to the effort of doing absolutely nothing.
- 1 MET: Sitting quietly on the couch.
- 3 METs: Burning three times as much as resting (like walking the dog).
- 8 METs: Burning eight times your resting rate (like running or hauling heavy boxes).
Our calculator lets you swap between Light, Moderate, and Vigorous for things like lifting or cycling. A lazy bike ride is not a hill climb. For things that don't change—like sleeping—we hide the toggle since the math is fixed.
Common Activities and Their MET Values
Just to give you a sense of scale, here's how researchers rank some standard movements:
- Sitting / Resting: 1.0 MET
- Walking (3 mph): 3.5 METs
- Weightlifting (Moderate): 3.5 METs
- Yoga: 3.0 to 4.0 METs
- Cycling (10-12 mph): 6.0 METs
- Running (6 mph): 9.8 METs
- Jumping Rope: 12.3 METs
Run your own numbers through the calculator to see what those multipliers actually mean for your body.
Fitness Trackers vs. Math: Which is Better?
If you check your Apple Watch after a workout, the calorie number usually won't match our math exactly.
Smartwatches rely heavily on your heart rate. That's great for cardio, but heart rate is easily tricked. If you drink two espressos, get stressed about an email, or work out in a hot garage, your heart rate spikes. Your watch thinks you're working harder and gives you more calories, even if you didn't do any extra physical work.
Math (BMR + METs) only cares about the mechanical work of moving your mass over a set time. It can't tell if you're out of shape and breathing hard, but it provides a much more stable, reliable baseline week-to-week—especially for lifting weights, where heart rate has almost nothing to do with calories burned.
Frequently Asked Questions
We start with your Basal Metabolic Rate (BMR)—what you burn doing absolutely nothing—using the Mifflin-St Jeor formula. Then we multiply that baseline by the Metabolic Equivalent of Task (MET) value for your chosen activity. It's far more accurate than throwing a generic multiplier at your bodyweight.
Yes, but the difference isn't magic. A pound of muscle burns about 6 calories a day at rest, while a pound of fat burns about 2. It adds up over time, which is why people with more muscle mass run slightly "hotter" metabolisms.
Physics. It takes more energy to move more mass. If you put 100 extra pounds in a backpack and tried to run a mile, you'd burn way more gas. Your body works the exact same way.
Definitely. Keeping your heart beating and lungs working isn't free. Sleeping has a MET value of 0.95, meaning an 8-hour night's sleep accounts for roughly a third of your daily calorie burn.
You don't need to chug a liter of water to recover from an hour of sitting at a desk. We only trigger the active hydration warning for Moderate or Vigorous activities, or stuff that legitimately makes you sweat.
Medical Disclaimer
Nutritional Advisory: These numbers are estimates based on the Mifflin-St Jeor equation and standard MET values. Everyone's metabolism is a little different depending on genetics, fitness level, and history. Use these numbers as a starting point. If you're starting a strict diet or intense training program, talk to a doctor or a registered dietitian first.
Data privacy: All calculations happen locally right here in your browser window. We don't save, track, or look at your numbers.
Last updated: April 2026 | Next scheduled review: April 2027