Calories Burned Calculator
Estimate calories burned in an activity from its MET value, your weight and time.
Results update as you type.
About this calculator
A calories-burned calculator estimates the energy an activity uses with the MET (Metabolic Equivalent of Task) method. One MET is roughly the energy of sitting still; an activity of 8 METs burns eight times that. Calories per minute = MET × 3.5 × weight(kg) ÷ 200, so heavier people and harder activities burn more.
Take a 70 kg person on a brisk 4 mph walk (4.3 METs). Calories per minute = 4.3 × 3.5 × 70 ÷ 200 ≈ 5.3, so a 45-minute walk burns about 237 calories. Swap in running at 6 mph (9.8 METs) and the same person burns roughly 12 calories a minute — more than double — because the MET value is higher. The tool lists common activities so you can compare them at your weight.
Pick the activity, enter your weight and duration, and use the result to plan training or estimate how exercise fits a calorie deficit. MET values come from the Compendium of Physical Activities and are population averages, so they ignore individual fitness, terrain and efficiency — treat the number as a good estimate rather than a precise count.
Frequently asked questions
What is a MET?
A MET (Metabolic Equivalent of Task) is a multiple of your resting energy use. Sitting quietly is 1 MET; a 5-MET activity burns five times as many calories. The values here come from the Compendium of Physical Activities.
How are calories burned calculated?
Calories per minute = MET × 3.5 × body weight in kg ÷ 200, multiplied by the number of minutes. It scales with both how hard the activity is and how much you weigh.
Why does body weight change the result?
Moving a heavier body costs more energy, so the same activity for the same time burns more calories for a heavier person. That is why weight is part of the formula.
How many calories does walking burn?
A brisk 4 mph walk is about 4.3 METs. For a 70 kg person that is roughly 5.3 calories a minute, so a 45-minute walk burns about 237 calories. Heavier people and faster paces burn more.
How many calories does running burn?
Running at 6 mph is about 9.8 METs — over twice a brisk walk. For a 70 kg person that is around 12 calories a minute, so 30 minutes burns roughly 360 calories.
Should I eat back the calories I burn?
That depends on your goal. In a weight-loss plan, eating back every burned calorie can erase your deficit; because the estimate has error, many people eat back only a portion of exercise calories.
API — use this calculator from code
Call this calculator as a free JSON endpoint — no key required. Send the field values below as query parameters or JSON. Read the full API docs →
Endpoint
GET https://calculator.free/api/v1/calories-burned/curl
curl "https://calculator.free/api/v1/calories-burned/?activity=4.3&units=metric&weight=70&minutes=45"JavaScript fetch()
const r = await fetch(
"https://calculator.free/api/v1/calories-burned/?" + new URLSearchParams({
"activity": "4.3",
"units": "metric",
"weight": "70",
"minutes": "45"
}));
const data = await r.json();
console.log(data.results);Results are estimates for general guidance only, not financial, medical or tax advice.