How to calculate the calories in food: a simple guide
Calculating calories starts with the values per 100 g printed on the label or listed in official nutrition tables.
The basic steps
- Find the value per 100 g on the label or in a nutrition table.
- Work out the proportion. If you eat 150 g, multiply:
calories_per_100g × 150 / 100. - Add up the ingredients. For a meal with several ingredients, calculate each one separately.
Free calculator
Use the BioBrief calorie calculator: search for the food, enter the grams and get kcal, protein, carbs and fat straight away.
Automatic scanning
For packaged products, the BioBrief app reads the label from a photo, which is faster than searching by hand. Here is how to scan a food label.