Every gram of protein has four calories every gram of fat has nine calaries and every gram of carbohydrates has four calaries. You should read the food labels. The labels show how may grams of fat protein and carbohydrates that particular dish has and you can calculate the total calories. Please pay attention to the serving sizes given in the label.

Please refer to the following link: https://www.webindia123.com/health/diet/calorie/calculation.htm