Hi Lakshya,
Treadmill is one of the wonderful way to burn calories. There are various preset programmes in treadmill like fat burn, cardio, interval training, manual ,etc.Programmes changes with companies. Manual is the best programme to start with for beginners or for the peoples who want to make their own programmes. While fat burning programmes is perfect for the peoples who have to burn a lot of calories. Calorie burning while running on treadmill depends on a lot factors like speed, frequency, your present fitness level, your weight, etc.SO depending on all these factors you would burn more or less calories.