How to Calculate Calories From Carbohydrates, Proteins and Fats

Use a food tracking app to help you count your daily intake of calories and macronutrients.
Image Credit: Eternity in an Instant/Stone/GettyImages

There are three macronutrients: carbohydrates, protein and fat. If someone is tracking their "macros," they're referring to these nutrients.

Advertisement

Video of the Day

These macros fit into a balanced diet. Eating a wide variety and enough of these helps you meet your nutritional targets for micronutrients like vitamins and minerals. You naturally eat foods that contain these nutrients at every meal, but you may want to know how much of each.

Some people aim for specific targets for their macronutrients and choose to track them or count them similar to counting calories. This can help with weight loss, weight gain and other fitness or nutritional goals. It's also generally helpful to see the breakdown of nutrients in the foods you're eating.

Advertisement

Counting calories can be challenging, and logging your macros can be too. Here's how to calculate the percentage of your calories that come from carbs, protein and fat.

Need an Easy Way to Track Your Macros?

Track your daily carb, protein and fat intake by logging your meals on the MyPlate app. Download now to fine-tune your diet today!

What Are Macronutrients?

Macronutrients are the nutrients your body needs the most in order to function. Because the body can't make enough of them on its own, it's essential that you get them from your diet, per August 2020 research in Nutrients.

Advertisement

Protein is found in muscle, bone, skin, hair and almost every other part of the body. It's used for many chemical reactions that keep you alive and it helps carry oxygen to your blood, according to the Harvard T.H. Chan School of Public Health.

Fats provide your body with essential fatty acids, which are used for brain development, controlling inflammation, regulating body temperature and blood clotting. Fats also help to keep your skin and hair healthy. They also help you absorb vitamins, according to the National Library of Medicine.

Advertisement

Carbohydrates, in short, are sugar molecules. The body breaks down carbs as the main source of energy for your cells, tissues and organs, per the National Library of Medicine.

Calculating Macro Percentages

Counting your macros may seem daunting at first, but after a while, it gets easier to tell which foods you should eat more (or less) of based on your nutritional goals. Here's how to do it.

Determine Your Nutritional Needs

Calculating your macronutrients is usually done to meet a specific goal.

If you're not sure what targets to aim for, the 2020-2025 Dietary Guidelines for Americans has a recommended dietary allowance for each of the three macronutrients.

Recommended Daily Amounts of Nutrients

Calories

Fat

Carbohydrates

Protein

Adults Assigned Female at Birth

1,600-2,000

20-35% of daily calories

45-65% of daily calories

10-35% of daily calories

Adults Assigned Male at Birth

1,800-2,400

20-35% of daily calories

45-65% of daily calories

10-35% of daily calories

Source: USDA

Calculate Your Total Intake of Calories

The first step to calculate any of the three macronutrients is to figure out the total amount of calories you ate and drank in a single day. You can do this by logging your food in a food diary or using an online calorie and nutrient counter like MyPlate.

Track Each Macronutrient Individually

Use a journal or online calorie counter to tally up your intake of each individual macronutrient. Count the number of carbohydrates, fat and protein you ate in grams. You should have three numbers in grams.

Determine How Many Calories Came From Each Macronutrient

Each macronutrient contains a different amount of calories, according to the USDA:

  • Carbohydrates: 4 calories per gram
  • Fat: 9 calories per gram
  • Protein: 4 calories per gram

You can use these figures to calculate the number of calories you took in of each macronutrient.

Here are some examples:

  • 65 grams of protein x 4 calories per gram = 260 total calories from protein
  • 200 grams of carbohydrates x 4 calories per gram = 800 total calories from carbohydrates
  • 60 grams of fat x 9 calories per gram = 540 total calories from fat

Divide Individual Macro Calories by Total Daily Calories

In the example above, the daily calories add up to 1,600. Take the number of calories from each macronutrient and divide it by the total amount of calories to get the percentages.

Here is what that calculation would look like using the example above:

  • Protein​: 260 calories from protein ÷ 1,600 daily calories = 16.25 percent of calories from protein
  • Carbs​: 800 calories from carbs ÷ 1,600 daily calories = 50 percent of calories from carbohydrates
  • Fat​: 540 calories from fat ÷ 1,600 daily calories = 33.75 percent of calories from fat

How to Calculate Percentage of Calories From Carbohydrates

To calculate the percentage of calories from carbohydrates, you'll need to know how many grams of carbohydrates you had in a day.

For example, one sweet potato contains 26 grams of carbohydrates, per the USDA. Do this for every food you eat.

Once you have the number of grams of carbohydrates you had, you can multiply it by 4 as there are 4 calories in every gram of carbs. If you had 200 grams of carbohydrates in a day, that would equate to 800 of your daily calories from carbohydrates.

You can then calculate the percentage of calories that came from carbs. Take the number of calories that came from carbohydrates and divide it by the total amount of calories you had in a day.

For a 1,600-calorie diet, divide 800 by 1,600 to determine the percentage of calories that come from carbs. In this example, 50 percent of calories come from carbohydrates.

How to Calculate Percentage of Calories From Protein

To calculate your daily calorie percentage from protein, start by adding up the number of grams of protein you had in a day.

You'll need to track every food you eat. For example, 1 cup of black beans contains 15 grams of protein, according to the USDA. Do this for all the foods you ate that day.

Once you have the total amount of grams of protein you had, you can multiply it by 4 as every gram of protein contains 4 calories. If you had 65 grams of protein in a day, that would add up to 260 calories from protein.

Take this number and divide it by the number of total calories you had in a day to get the percentage of calories that came from protein. For a 1,600-calorie diet, divide 260 by 1,600. This would equate to 16.25 percent of calories coming from protein.

How to Calculate Percentage of Calories From Fat

Log your daily intake of food and add up the number of grams of fat you had in a day.

For example, half an avocado contains 15 grams of fat, according to the USDA. You'll need to do this for every food you ate that day from breakfast to dinner.

Once you've calculated the number of grams of fat you ate, multiply that figure by 9 as there are 9 calories in every gram of fat. If you had 60 grams of fat, that would mean 540 of your calorie intake came from fat.

You can then take this number of calories coming from fat and divide it by the total number of calories had in a day. For a 1,600-calorie diet, divide 540 by 1,600. This gives you 33.75 percent of calories coming from fat.

What Is the 4-9-4 Rule?

The 4-9-4 rule is a simple way to calculate the number of calories you'll get from each macronutrient in a food. To use the 4-9-4 rule, check your nutrition label and follow these formulas:

  • Find "Total Carbohydrates" and multiply the amount by 4. This will give you the number of calories in the food that comes from carbs.
  • Find "Total Fat" and multiply the amount by 9. This will give you the number of calories in the food that comes from fat.
  • Find "Protein" and multiply the amount by 4. This will give you the number of calories in the food that comes from protein.

If you add all three of these amounts, you should get the total number of calories in the food.

Advertisement

references