Your watch shows one calorie number, the gym machine shows another, and neither explains where it came from. This calculator uses standard MET values from exercise research to estimate calories burned for common activities, based on your weight and how long you exercised.

Calories Burned Calculator

How Calories Burned Are Calculated

This calculator uses MET values, short for metabolic equivalent of task. One MET is roughly the energy you use sitting quietly. An activity with a MET value of 8 burns about eight times that. The formula is:

Calories per minute = MET x 3.5 x body weight in kg / 200

The MET values come from the Compendium of Physical Activities, a reference used widely in exercise research. Because they are averages, your real burn can be higher or lower depending on fitness, technique, and effort.

Calories Burned in 30 Minutes by Activity

Activity 130 lb Person 155 lb Person 185 lb Person
Walking, brisk (4 mph) about 155 about 185 about 220
Cycling, moderate about 250 about 295 about 350
Running, 10 min/mile about 305 about 360 about 430
Strength training, vigorous about 185 about 220 about 265
Swimming laps, moderate about 215 about 260 about 310
Yoga, hatha about 75 about 90 about 110

Why Your Watch Shows a Different Number

Wearables estimate calories by combining heart rate, motion, and your profile data, so they can adjust for how hard you actually worked. That often makes them more personal than a MET table, but also more variable. Studies comparing wrist devices with lab measurements have found calorie errors of 20% or more, even when heart rate readings were accurate.

Another common source of confusion is active versus total calories. Some apps report only the extra calories burned by exercise, while others include the calories you would have burned anyway at rest. A MET-based figure like the one above is a total.

For heart rate based tracking, make sure your zones are set correctly with our Heart Rate Zone Calculator, and see how your daily steps add up with the Steps to Miles Calculator.

Getting More Accurate Numbers

  • Keep your weight, height, and age up to date in your wearable’s app.
  • Wear the watch snug, about a finger’s width above the wrist bone, during workouts.
  • Use a chest strap for strength training and intervals, where wrist sensors struggle most.
  • Compare trends over weeks instead of trusting a single workout total.

Disclaimer: Calorie figures are estimates based on published MET values. It is not medical advice. Talk with a healthcare provider before making major changes to your exercise, diet, or sleep, especially if you have a health condition or take medication.