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Grams To Calories Calculator

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Grams to calories conversionHow many calories in a gram of carbohydrate?How many calories are in a gram of protein?How many calories in a gram of fat?How do I calculate calories from alcohol?Is calorie (cal) and kilocalorie (kcal) the same?Convert grams to calories - practical exampleFAQs

The grams to calories calculator is a simple tool that allows you to convert the amount of macronutrients (expressed in grams) into calories. The article below shows how to convert grams to calories and how many calories there are in a gram of carbohydrate, protein, fat, and alcohol.

Not sure how many grams of each macronutrient you should consume daily? Check out our macro calculator!

Grams to calories conversion

Almost all food labels have information stating the number of total calories and grams of macronutrients, but you will rarely see the number of calories from each macronutrient. This grams to calories calculator helps you to understand the difference between calories and grams, and learn the conversion rules.

Knowing how to convert grams to calories allows you to:

How many calories in a gram of carbohydrate?

Carbohydrates consumed in food provide 3.87 kcal of energy per gram for simple sugars, and 3.57 - 4.12 kcal per gram for complex carbohydrates. These values are usually rounded to 4 kcal per gram of carbohydrate to simplify the calculation.

Carbohydrates are the main source of energy in the human diet. They include sugars, starches, and fiber.

How many calories are in a gram of protein?

1 gram of protein provides approximately 4 kcal. Proteins are every animal cell's major functional and structural component. They consist of amino acids, some of which humans cannot synthesize. It means you must obtain proteins from your diet.

How many calories in a gram of fat?

Fat is the most energy-dense macronutrient - 1 gram provides 9 kcal.

You need fats for the construction and maintenance of cell membranes, to maintain a stable body temperature, and to supply fat-soluble vitamins.

How do I calculate calories from alcohol?

Follow these steps:

  1. Remember how many calories there are in a gram of alcohol: 7 calories per gram.
  2. Determine the amount of alcohol in grams. If it is not on the label, use the formula: alcohol [g] = volume [mL] × alcohol by volume [%] × 0.78924 [g/mL].
  3. Multiply the result of Step 2 by the number of calories per gram of alcohol, that is, by 7.
  4. For instance, 50 mL of vodka contains 7 [kcal/g] × 50 [mL] × 0.40 × 0.78924 [g/mL] = 110 kcal. Cheers!

Is calorie (cal) and kilocalorie (kcal) the same?

There are two main definitions of a calorie:

  1. Small calorie or gram calorie (we usually denote it as cal).
  2. Large calorie, food calorie, or kilocalorie (which we present as Cal, calorie, or kcal).

However, the phrases grams to calories and grams to kcal sometimes mean the same thing. In nutrition, we commonly use the word calorie to mean the number of kilocalories (kcal) when providing nutritional information.

Therefore, our grams to calories calculator uses the phrases grams to calories and grams to kcal interchangeably.

Convert grams to calories - practical example

Let's convert grams to calories using the following nutritional information as an example.









To calculate the number of calories in this food product, you need to use the appropriate conversion rate for each macronutrient:

Carbohydrate: 4 kcal × 23 = 92 kcal

Protein: 4 kcal × 4 = 16 kcal

Fat: 9 kcal × 9 = 81 kcal

Total: 92 kcal + 16 kcal + 81 kcal = 189 kcal

This product contains 189 kcal. But what can you use this information for?


  • If you calculate the calories in each macronutrient consumed, you will find it easier to track your intake if you are trying to maintain, lose, or gain weight. You can also check our maintenance calorie calculator to calculate how many calories your body needs to maintain your current weight.

How many calories in a pint of beer?

There are about 160-180 kcal in a pint of beer, depending on the beer type. To arrive at this answer, estimate the calories coming from the alcohol content (each gram provides 7 kcal, so a pint of 5% beer is about 130 kcal) and add the calories coming from carbs (each gram is roughly 4 kcal): as there are about 10 g of carbs is a pint of beer, they amount to 40 kcal.

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