How do you calculate macros?”

This is one of the most common questions I’m asked about dieting, and it’s one of the most important ones to answer if you want to build a body you can be proud of. 

For those of you who aren’t au fait, the term “macros” refers to protein, carbs, and fat, and “calculating macros” is the process of determining how much of each you should eat to reach your health and fitness goals.

Many people think that calculating macros requires you to unravel a Gordian knot of numbers, but this isn’t the case.

Using the simple formulas outlined in this article, you can learn how to calculate macros to lose weight, gain weight, or maintain weight in less than 30 seconds (seriously).

Let’s dive in.

What Are Macros?

A macronutrient (“macro”) is a nutrient that your body needs in large amounts to survive, with the main ones being protein, carbs, and fat. Learning how to calculate your macros is important because, along with counting calories, tracking how much of each macronutrient you eat is the best way to control and improve your body composition.

To understand the role protein, carbs, and fat play in helping you gain or maintain muscle, lose fat, and stay healthy, let’s look at each.

Protein

The primary reason to eat protein is to provide your body with adequate essential amino acids so that it can build and repair cells. Protein contains four calories per gram and you can find it in large amounts in foods such as lean meat, fish, Greek or Icelandic yogurt, cheese, eggs, and pulses.

Carbohydrates

There are three main types of carbohydrates: Sugar, starch, and fiber. The body breaks down sugar and starch into glucose, the main energy source for the brain, central nervous system, and red blood cells, while fiber helps you stay satiated and maintain good digestive health. 

Like protein, carbs contain four calories per gram and you can find them in large amounts in foods such as vegetables, fruits, grains, tubers, and cereals.

Fat

Dietary fat has several crucial functions in the body, including optimizing your immune system, building cells (especially nerve cells), and providing energy. Fat contains the most calories of any macronutrient, providing nine calories per gram. High-fat foods include oils, nuts and nut butters, seeds, and fatty meat, fish, and dairy products.

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How to Calculate Macros for Weight Loss

As you’ll soon see, learning how to calculate macros for fat loss isn’t as difficult as many people make it out to be.

That said, if you’d like to skip the math, just take the Legion Diet Quiz, and in less than a minute, you’ll know exactly how much of each macronutrient you should eat to get the body you want. Click here to check it out.

Otherwise, let’s get started.

Calculate Your Cutting Calories

If you want to lose weight, you have to consistently eat fewer calories than you burn (calories in versus calories out).

When “cutting” (dieting to lose weight), eating between 8-to-12 calories per pound of body weight per day creates a 20-to-25 % calorie deficit for most people, which is a good target to aim for to lose fat quickly and healthily.

You should choose the low or high end of that range based on how physically active you are:

  • If you’re sedentary (little to no exercise or vigorous physical activity),  choose the lowest number (8 calories per pound of body weight per day). 
  • If you’re lightly active (one-to-three hours of exercise or vigorous physical activity per week), choose the middle of the range (9-to-10 calories per pound of body weight per day). 
  • If you’re moderately active (four-to-seven hours of exercise or vigorous physical activity per week), choose the highest number (12 calories per pound of body weight per day). 
  • If you’re very active (eight or more hours of exercise or vigorous physical activity per week), you’ll likely want to eat more than 12 calories per pound of body weight per day when cutting—14 or even 16 depending on how much energy you burn per day on average. Since activity levels can vary quite a bit, use the Legion Calorie Calculator to dial in the right number of calories for you.

I didn’t pick this 20-to-25% number out of thin air, either. As I explain in my fitness books for men and women, Bigger Leaner Stronger and Thinner Leaner Stronger, studies show that it works tremendously well for both fat loss and muscle preservation when combined with resistance training and high protein intake.

Calculate Your Cutting Macros

To learn how to calculate macros for cutting follow these simple recommendations:

  • Consume 1-to-1.2 grams of protein per pound of body weight per day, and if you’re very overweight, 0.6-to-0.8 grams per pound of body weight per day is sufficient. This usually comes out to around 30-to-40% of daily calories.
  • Consume 30-to-50% of your daily calories from carbohydrate, which comes out to about 0.75-to-2 grams of carbs per pound of body weight per day for most people.
  • Consume 20-to-30% of daily calories from fat, which is 0.2-to-0.4 grams of fat per pound of body weight per day for most people.

Let’s look at how to put all of this together. Firstly, here’s how to do the math for someone who is lightly active:

  1. Body weight in pounds x 9-to-10 = total calories per day
  2. Body weight in pounds x 1-to-1.2 = grams of protein per day
  3. Grams of protein per day x 4 = calories from protein per day
  4. Total calories per day x 0.3-to-0.5 = calories from carbs per day
  5. Calories from carbs per day ÷ 4 = grams of carbs per day
  6. Total calories per day – (calories from protein per day + calories from carbs per day) = calories from fat per day
  7. Calories from fat per day ÷ 9 = grams of fat per day

And now let’s look at how this works in practice using a lightly active 180-pound man named Joe who wants to lose fat. In this example, Joe has decided to . . .

  • Consume 1 gram of protein per pound of body weight
  • Get 40% of his calories from carbs
  • Get his remaining calories from fat

Here’s how the math looks:

  1. 180 x 10 = 1,800 calories per day
  2. 180 x 1 = 180 grams of protein per day
  3. 180 x 4 = 720 calories from protein per day
  4. 1,800 x 0.4 = 720 calories from carbs per day
  5. 720 ÷ 4 = 180 grams of carbs per day
  6. 1,800 – (720 + 720) = 360 calories from fat per day
  7. 360 ÷ 9 = 40 grams of fat per day

Thus, Joe would want to eat 1,800 calories, 180 grams of protein, 180 grams of carbs, and 40 grams of fat per day to lose fat.

How to Calculate Macros for Muscle Gain

Like calculating cutting macros, calculating macros for lean gaining isn’t rocket science (it’s nutrition science, technically).

And remember that if crunching numbers isn’t your bag, just take the Legion Diet Quiz, and in less than a minute, you’ll know how many calories, how much of each macronutrient, and which foods you should eat to reach your goals. Click here to check it out.

If you’d like to get into the nitty gritty, though, here’s how to calculate macros for muscle gain the old-fangled way.

Calculate Your Lean Gaining Calories

Research shows that the sweet spot for maximizing muscle gain while minimizing fat gain is somewhere around 110% of your total daily energy expenditure. 

Thus, my recommendation for calibrating calories when lean gaining is to maintain a calorie surplus of about 10%. For most people, this comes out to 16-to-18 calories per pound of body weight per day.

As with cutting, you should choose your number based on how physically active you are. 

  • If you’re sedentary (no exercise or vigorous activity), you shouldn’t be lean gaining because extra calories without resistance training just makes you fatter. 
  • If you’re lightly active (one-to-three hours of exercise or vigorous activity per week), start with 16 (and try to do at least three strength training workouts per week).
  • If you’re moderately active (five or more hours of exercise or vigorous activity per week), go with 17, and then if you aren’t steadily gaining weight and strength, move up to 18.
  • If you’re very active (eight or more hours of exercise or vigorous physical activity per week), use the Legion Calorie Calculator to determine how many calories you should eat when lean gaining.

Calculate Your Lean Gaining Macros

To maximize muscle building while you lean gain, follow these recommendations:

  • Consume 0.8-to-1 gram of protein per pound of body weight per day.
  • Consume 30-to-50% of your daily calories from carbohydrate, which comes out to about 0.75-to-2 grams of carbs per pound of body weight per day for most people.
  • Consume 20-to-30% of daily calories from fat, which is 0.2-to-0.4 grams of fat per pound of body weight per day for most people.

Here’s how to do the math for someone who’s moderately active:

  1. Body weight in pounds x 17-to-18 = total calories per day
  2. Body weight in pounds x 0.8-to-1 = grams of protein per day
  3. Grams of protein per day x 4 = calories from protein per day
  4. Total calories per day x 0.3-to-0.5 = calories from carbs per day
  5. Calories from carbs ÷ 4 = grams of carbs per day
  6. Total calories per day – (calories from protein per day + calories from carbs per day) = calories from fat per day
  7. Calories from fat per day ÷ 9 = grams of fat per day

And now let’s look at how this works in practice using a moderately active 120-pound woman named Jane who wants to build muscle. In this example, Jane has decided to . . .

  • Consume 1 gram of protein per pound of body weight
  • Get 50% of her calories from carbs
  • Get her remaining calories from fat

Here’s how the math looks:

  1. 120 x 17 = 2,040 calories per day
  2. 120 x 1 = 120 grams of protein per day
  3. 120 x 4 = 480 calories from protein per day
  4. 2,040 x 0.5 = 1,020 calories from carbs per day
  5. 1,020 ÷ 4 = 255 grams of carbs per day
  6. 2,040 – (480 + 1,020) = 540 calories from fat per day
  7. 540 ÷ 9 = 60 grams of fat per day

Thus, Jane would want to eat 2,040 calories, 120 grams of protein, 255 grams of carbs, and 60 grams of fat per day to build muscle.

How to Calculate Macros for Maintaining

The following guide makes calculating macros for weight maintenance simple, but if you don’t do numbers, you can get specific advice about how many calories, how much of each macronutrient, and which foods you should eat to reach your health and fitness goals by taking the Legion Diet Quiz.

If you’d like to learn the logic the quiz uses to compute your results, though, keep reading.

Calculate Your Maintenance Calories

Twelve-to-sixteen calories per pound of body weight per day is the sweet spot for most people when maintaining. More specifically:

  • If you’re sedentary, eat 12 calories per pound of body weight per day (and start training!).
  • If you’re lightly active, eat 13-to-14 calories per pound of body weight per day.
  • If you’re moderately active, eat 15-to-16 calories per pound of body weight per day.
  • If you’re very active, use the Legion Calorie Calculator to determine how many calories you should eat when maintaining.

Calculate Your Maintenance Macros

Here’s how to calculate your macros while maintaining:

  • Consume 0.8-to-1 gram of protein per pound of body weight per day.
  • Consume 30-to-50% of your daily calories from carbohydrate, which comes out to about 0.75-to-2 grams of carbs per pound of body weight per day for most people.
  • Consume 20-to-30% of daily calories from fat, which is 0.2-to-0.4 grams of fat per pound of body weight per day for most people.

Here’s how to do the math for someone who’s lightly active:

  1. Body weight in pounds x 13-to-14 = total calories per day
  2. Body weight in pounds x 0.8-to-1 = grams of protein per day
  3. Grams of protein per day x 4 = calories from protein per day
  4. Total calories per day x 0.3-to-0.5 = calories from carbs per day
  5. Calories from carbs per day ÷ 4 = grams of carbs per day
  6. Total calories per day – (calories from protein per day + calories from carbs per day) = calories from fat per day
  7. Calories from fat per day ÷ 9 = grams of fat per day

And now let’s look at how this works in practice using a lightly active 170-pound man named Jon who wants to maintain his weight. In this example, Jon has decided to . . .

  • Consume 1 gram of protein per pound of body weight
  • Get 40% of his calories from carbs
  • Get his remaining calories from fat

Here’s the working out:

  1. 170 x 13 = 2,210 calories per day
  2. 170 x 1 = 170 grams of protein per day
  3. 170 x 4 = 680 calories from protein per day
  4. 2,210 x 0.4 = 884 rounded down to 880 calories from carbs per day
  5. 880 ÷ 4 = 220 grams of carbs per day
  6. 2,210 – (680 + 880) = 650 calories from fat per day
  7. 650 ÷ 9 = 72 rounded down to 70 grams of fat per day

Thus, Jon would want to eat 2,210 calories, 170 grams of protein, 220 grams of carbs, and 70 grams of fat per day to maintain his weight.

FAQ #1: How do I calculate macros for weight loss and muscle gain?

Building muscle and losing fat simultaneously is known as “body recomposition,” and it’s only a viable strategy for people who’ve been following a weightlifting program for less than one year.

To successfully “recomp,” you should maintain a small calorie deficit of 10-to-15% per day.

This range is based on several studies that have looked at the relationship between calorie restriction, fat loss, and muscle growth, which have found that if you restrict your calories much more than this, it’s very difficult to build an appreciable amount of muscle.

The leaner you are, the smaller your calorie deficit should be. This is because your risk of muscle loss increases (and your ability to build muscle decreases), as your body fat levels drop.

If you’re at or below 10% body fat as a man or 20% as a woman, aim for the lower end of this range (a 10% calorie deficit). If you’re above 10/20% body fat, aim for the upper end of this range (a 15% calorie deficit).

For most people, this means consuming around 10-to-14 calories per pound of body weight per day. 

Since successfully “recomping” requires precise control of your calorie intake, it’s best to calculate your TDEE and then subtract 10-to-15% from this number instead of using multipliers of body weight as explained in the previous steps.

Once you know how many calories to eat, split your protein, carbs, and fat according to the guidelines for cutting as explained in the above section on calculating your cutting macros. 

FAQ #2: How do I calculate my macros with a macro calculator?

To calculate macros using a macro calculator, input your sex, weight, height, age, and activity level in the fields provided, and the calculator will do all the of the number crunching for you.

Check out the Legion Macronutrient calculator here.

FAQ #3: How do I calculate macros for keto?

Most keto diets require you to eat 50 grams of carbs per day or fewer. Since carbs contain four calories per gram, this means you can eat no more than 200 calories from carbs per day. 

With that in mind, you can calculate your keto macros for cutting, lean gaining, or maintaining using the steps above. Just bear in mind you should keep carbs to 50 grams (or 200 calories) per day or less. 

FAQ #4: How do you calculate how many macros to eat?

The three basic steps involved in calculating macros are:

  1. Decide whether you want to lose fat, build muscle, or maintain your weight.
  2. Determine how many calories you need to consume to reach your goal (a quick way to do this is using the Legion Calorie Calculator here).
  3. Split the calories you can consume into macros (amounts of protein, carbs, and fat) that help you reach your goal. You can do this using the information in this article, or you can take the Legion Diet Quiz, which calculates everything for you.

FAQ #5: How do you calculate macros in food?

Packaged food should have a breakdown of how many calories and how much protein, carbs, and fat the food contains on the label.

If the food isn’t prepackaged (fresh fruit and vegetables, for example), you can get calorie and macronutrient information from resources such as . . .

+ Scientific References