The number of calories you burn while training on an exercise bike depends on a few factors, including your weight, intensity of your workout, and duration of your workout. A general estimate is that you can burn between 200 and 400 calories in 30 minutes of moderate-intensity biking. If you increase the intensity of your workout, you can burn even more calories. For example, if you ride at a vigorous pace for 30 minutes, you could burn between 300 and 600 calories. And if you ride at a very high intensity for 30 minutes, you could burn up to 1000 calories. So, whether you're looking to lose weight, tone up, or just improve your overall fitness, biking is a great way to do it!