Calories Burned Calculator

How the estimate works

Researchers have measured the oxygen people use during hundreds of activities and collected the results in the Compendium of Physical Activities, updated most recently in 2024. Each activity gets a MET value (metabolic equivalent of task): how many times more energy it takes than sitting quietly. Sitting is 1 MET, brisk walking at 3.5–3.9 mph is 4.8 METs, running at 6 mph is 9.3 METs.

The Compendium defines 1 MET as an oxygen uptake of 3.5 mL per kilogram of body weight per minute, roughly 1 kcal per kilogram per hour. Because the value is per kilogram, a heavier person burns more calories doing the same activity for the same time. The calculator multiplies the MET value by your weight and the time you spent, then converts oxygen into calories.

The 50 activities here are a selection of common ones, each with its five-digit Compendium code shown under the menu so you can look it up. Choose the entry closest to how hard you actually worked: walking alone ranges from 2.8 METs at a slow pace to 5.5 METs when very brisk.

This is not the same as the calorie calculator, which estimates how much energy you use across a whole day to set an eating target, or the BMR calculator, which covers only the energy used at rest. This page isolates one session of activity.

Formula

MET

the activity’s value from the 2024 Adult Compendium

3.5

mL of oxygen per kg per minute in one MET

÷ 200

converts mL of oxygen to kcal, using about 5 kcal per litre of oxygen (÷ 1000 × 5)

This is the form used in exercise physiology textbooks and by the American College of Sports Medicine. Using the other definition, 1 MET = 1 kcal/kg/h, gives results about 5% lower, because 3.5 mL × 60 min × 5 kcal/L = 1.05 kcal/kg/h.

Net calories use (MET − 1) instead of MET. They subtract the energy you would have used anyway just by being alive and sitting, which is the fairer number when you want to know what the activity added to your day.

Worked examples

A person who weighs 160 lb walks briskly (3.5–3.9 mph, 4.8 METs) for 30 minutes:

1. Weight: 160 × 0.45359237 = 72.57 kg
2. Per minute: 4.8 × 3.5 × 72.57 ÷ 200 = 6.10 kcal
3. For 30 minutes: 6.10 × 30 = 183 kcal
4. Net: (4.8 − 1) × 3.5 × 72.57 ÷ 200 × 30 = 145 kcal above sitting quietly

A 70 kg person running at 6 mph (10 min/mile, 9.3 METs) for 45 minutes: 9.3 × 3.5 × 70 ÷ 200 = 11.39 kcal per minute, so about 513 kcal in total and 458 kcal net.

Why your real number will differ

• MET values are averages. The Compendium values come from groups of adults in studies. Its authors describe it as a starting point that does not reflect precise individual energy use; fitness, skill, technique, terrain and body composition all shift the real cost.
• The resting value is too high for many people. The 3.5 mL/kg/min figure goes back to one 40-year-old, 70 kg man. In a study of 769 adults, measured resting oxygen uptake averaged 2.6 mL/kg/min, so the standard MET overestimated it by about 35% on average (Byrne et al., 2005). Body composition explained most of the difference between people.
• Only the time you are moving counts. Downhill skiing values are for active time only, and rests between sets or games lower the real average. Enter the active minutes.
• Afterburn is not included. Energy used in recovery after hard exercise is not part of a MET value.