Weigh yourself to get an accurate reading of your weight. If your scale measures weight in pounds, multiply the number by .45 to convert it to kilograms (for example, 120 lb. x .45 = 54 kg).
Keep track of your level of effort during a workout. Compare your average exertion on the elliptical machine to walking, jogging or running.
Examine a list of MET rates and determine which number best corresponds to your exertion (see Resources). You will likely choose a number between four and eight.
Record the length of your workout in portions of an hour (for example a 20-minute workout would be recorded as .33 of an hour).
Multiply your weight in kilograms by the MET rate you chose (for example, 54 kg x 6 = 324).
Multiply the resulting number from the previous step by the portion of an hour that you worked out to get your total calories burned (for example, 324 x .33 = 107 calories).