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A Simple and Accurate Macronutrient Calculator (and How to Use It)

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A Simple and Accurate Macronutrient Calculator (and How to Use It)

If you want to calculate your macronutrients for losing, gaining, or maintaining weight, you want to read this article (and use this calculator).


When it comes to losing fat and building muscle, you probably know that exercise alone isn’t going to get you there.

Your diet is ultimately going to determine your progress.

Think of it this way:

If your body were a car, exercise is the gas pedal and diet is the brake.

You have to exercise to get your physique moving in the right direction…

…but how far are you going to get with your foot on the brake?

Not very far…and eventually your engine will burn out.

The bottom line is this:

  • Get your diet right and you’ll find that burning fat and building muscle is simple and straightforward.
  • Get it wrong, however, and you’ll find it mystifyingly hard…if not impossible.

Unfortunately, many more people are getting it wrong than right.

They’re lost in the kaleidoscopic funhouse of mainstream diet nonsense, wandering in circles.

If you feel the same way, take heart: this is article is going to show you the path out.

It’s going to teach you the easiest and most effective way to “diet”: macronutrient-based dieting.

(Also known as “flexible dieting.”)

Imagine if you could get the body you want with…

  • no food restrictions,
  • no set meal times,
  • no starving yourself,
  • no low-carb misery,
  • and no battling with hunger and cravings.

Well, you can make that fantasy a reality, and this article will show you how.

Read on.

The Macronutrient Calculator

calorie calculator

I’m going to start this article with the calculator in case you’re already familiar with the most important aspects of dieting (energy balance and macronutrient breakdown) and so you can get back to it easily and quickly in the future.

And if you need a bit of help understanding the calculator and how to use it to create meal plans that actually work, then keep reading!

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What is a “Macronutrient” Anyway?

what are macros

The dictionary defines “macronutrient” in the following way:

A macronutrient is any of the nutritional components of the diet that are required in relatively large amounts: protein, carbohydrate, fat, and minerals such as calcium, zinc, iron, magnesium, and phosphorous.

(Most people think of “macros” as just protein, carbohydrate, and fat, but technically it includes the macrominerals as well.)

When it comes to diet and meal planning, the macronutrients you pay most attention to are protein, carbohydrate, and fat.

Understanding the “Macronutrient” Style of Dieting

flexible dieting

If you’ve spent any time cruising the Instagram profiles of fitness folk, you’ve likely seen talk of food in relation to its “macros”…

…and you’ve probably been a little baffled.

How the hell do these people look the way they do eating the foods they eat?

It must be a hoax, right?

They don’t actually eat that pile of pancakes or bowl of Oreo ice cream…they must be just snapping photos to look cool.

Or maybe these graphic displays of “unclean eating” are the exception. The only cheat meal of the month or something?

If you’ve had thoughts like these, I understand.

I was just as skeptical when I first heard that, as far as body composition goes, what you eat isn’t nearly as important as how much.

That is, the caloric and macronutrient content of food determines our physiques more than anything else.

Let’s break this into two parts–calories and macronutrients–and learn a bit more about the role each plays in our diets.

Use this workout and flexible dieting program to lose up to 10 pounds of fat and build muscle in just 30 days…without starving yourself or living in the gym.

Energy Balance Determines Your Caloric Needs


If you want to know how caloric intake relates to body composition, then you need a basic understanding of the scientific principles of “energy balance.”

Energy balance is the relationship between the energy you feed your body and the energy it expends.

As you probably know, this is often measured in kilocalories.

(A “calorie” is just a measurement of energy. One calorie is the amount of energy it takes to heat one kilogram of water one degree Celsius.)

You see, the scientifically validated, “boring” reality is this:

  • Meaningful weight loss requires you to expend more energy than you consume.
  • And meaningful weight gain (both fat and muscle) requires the opposite: more consumption than expenditure.

If you’re shaking your head, thinking I’m drinking decades-old Kool-Aid, let me ask you a few questions.

Why has every single controlled weight loss study conducted in the last 100 years…including countless meta-analyses and systematic reviews…concluded that meaningful weight loss requires energy expenditure to exceed energy intake?

Why have bodybuilders dating back just as far…from Sandow to Reeves and all the way up the line…been using this knowledge to systematically and routinely reduce and increase body fat levels?

And why do new brands of “calorie denying” come and go every year, failing to gain acceptance in the weight loss literature?

The reality is a century of metabolic research has proven, beyond the shadow of a doubt, that energy balance, which operates according to the first law of thermodynamics, is the basic mechanism that regulates fat storage and reduction.

That doesn’t mean you have to count calories to lose weight…but it does mean you have to understand the relationship between calorie intake and expenditure and weight gain and loss.

This is why claims that some foods are “better” than other for losing weight is misleading.

It misses the forest for the trees because foods don’t have any special properties that make them better or worse for weight loss.

What they do have, however, are varying amounts of calories and varying types of macronutrient profiles.

These two factors–the calories contained in foods and how those calories break down into protein, carbohydrate, and fat–are what make certain foods more suitable for losing weight than others.

Notice I said more suitable, and not “best.”

And that’s because if you know how to regulate and balance your food intake properly, you can eat just about anything and lose weight.

Don’t believe me?

Well, Professor Mark Haub lost 27 pounds on a diet of protein shakes, Twinkies, Doritos, Oreos, and Little Debbie snacks.

He did this to prove a simple point:

If you consistently feed your body less energy than it burns, you’ll lose weight, even if that energy comes from convenience store fare.

Let’s not forget the corollary, either:

If you consistently feed your body more energy than it burns, you’ll gain weight, even if that energy comes from the “cleanest” foods on the planet.

Just look around your gym for proof of this one.

How many of these people are overweight regardless of how nutritiously they eat?

So, that’s calories and energy balance and how you can use them to reduce or increase body weight.

How do macronutrients fit into this picture?

How to Get Your “Macros” Right

macronutrient ratio

You’ve already seen that as far weight loss and gain goes, a calorie is a calorie.

Eat too much of anything–even organic, non-GMO, gluten-free, sugar-free vegetable goop–and you will gain weight.

Maintain a calorie deficit while following a “gas station diet” of the most nutritionally bankrupt crap you can find and you will lose weight.

When it comes to optimizing body composition, though, a calorie is not a calorie.













When you want to build muscle and lose fat (or minimize fat gain), your food choices matter. Well, not the specific foods per se, but how they break down macronutritionally.

You see, people say they want to lose or gain “weight,” but that’s not what they mean.

The goal is never to just lose or gain weight. It’s to lose fat and not muscle and gain muscle and not fat. And when that’s the goal, some types of calories are now much more important than others.

Protein, for instance, provides the same amount of calories per gram as carbohydrate, but is far more important for building muscle and losing fat.

Eating like Professor Haub did will no longer cut it.

Instead, you will need to ensure you balance your protein, carbohydrate, and fat intake properly.

The Most Important Macronutrient: Protein

macronutrient calculator for cutting

If you want a strong, lean body that you can maintain with ease, then you want to make sure you’re eating enough protein.

There are quite a few reasons for this, but here are the highlights:

Your protein intake is even more important if you’re exercising regularly because this further increases your body’s need for amino acids.

If you want to know how much protein you should be eating to build muscle and lose fat, check out this article.

Why You Should (Probably) Eat a Lot of Carbs

macronutrient calculator bodybuilding

Ask Google how many carbs you should eat, weed out the idiots, and you’re left with a lot of contradictory answers.

Many well-respected health and fitness authorities argue why low-carb dieting is the way of the future.

Many others rail against it as just another fad.

Many still are in the middle saying “it depends…”

Well, here’s my position:

If you’re healthy and physically active, and especially if you lift weights regularly, you’re probably going to do best with more carbs, not less.

And yes, that applies to both building muscle and losing fat. The reality is a relatively high carbohydrate intake can help you do both.

Check out this article to learn more.

How Much Dietary Fat You Actually Need

macronutrient calculator for athletes

Remember when low-fat dieting was all the rage?

When fat-free products flooded the supermarkets and “gurus” used to say that dietary fats made you fat?

Well, that pendulum has swung hard in the other direction.

Now we’re told that carbohydrates are the real enemy and that we should be eating copious amounts of dietary fat if we want to be healthy, lean, and strong.

What gives?

Well, the truth is dietary fats play a vital role in the body.

They’re used in processes related to cell maintenance, hormone production, insulin sensitivity, and more.

If fat intake is too low, these functions can become compromised, which is why the Institute of Medicine recommends that adults should get 20 to 35% of their daily calories from dietary fat.

That said, those percentages were worked out for the average sedentary person, who often eats quite a bit less than someone that exercises regularly.

And even more so if that person has a higher than average amount of muscle mass.

For example, a 190-pound sedentary male with a normal amount of lean mass would burn around 2,000 calories per day.

Based on that, the IoM’s research says he would need 45 to 80 grams of fat per day. That makes sense.

Now, I weigh about 190 pounds…but I also have a lot more muscle than the average person and I exercise about 6 hours per week.

Thus, my body burns about 3,000 calories per day and if I were to blindly apply the IoM’s research to that number, my recommended fat intake would skyrocket to 65 to 115 grams per day.

But does my body really need that much more dietary fat simply because I’m muscular and burn a lot of energy through regular exercise?

No, it doesn’t.

Based on the research I’ve seen, if dietary fat comprises 20 to 35% of your basal metabolic rate (around 0.3 grams per pound of fat-free mass), you’ll be fine.

Putting It All Together


We’ve touched on quite a bit so before I move on to the macro calculator, I think a recap will help.

  • The most important aspect of dieting is energy in versus energy out (energy balance).

An energy deficit results in weight loss and a surplus in weight gain.

  • Next in importance is how those calories break down into protein, carbs, and fats.

You want to eat enough protein and tailor your carbohydrate and fat intake to your circumstances and goals.

  • Last in importance are the actual foods providing the calories and macronutrients.

The reason to eat “clean” foods is not to help with weight loss or gain but to provide the body with vital micronutrients.

This supports and preserves health.

Thus, an overall strategy emerges:

Calculate your caloric intake, break it down into “macros,” and build a meal plan that provides the majority (80%+) of those calories and macros from nutritious foods.

This is the heart of “flexible dieting.” Do it and you can’t lose.

And you can get started right away with the macronutrient calculator at the top of this page.

How to Calculate Your Macronutrients

macronutrient food calculator

As you probably saw, the macro calculator has several elements.

You input your weight, (approximate) body fat percentage, and activity multiplier and it shows you your basal metabolic rate (BMR) and total daily energy expenditure (TDEE), and then lets you set your macros.

Let’s quickly go over each of these functions.

(Basal Metabolic Rate) BMR

Your basal metabolic rate is the amount of energy your body burns at rest.

It’s the minimum amount of energy it costs to stay alive.

It’s called this because basal means “forming a base; fundamental” and metabolic means “related to the metabolism,” which is “the physical and chemical processes in an organism by which it produces, maintains, and destroys material substances, and by which it makes energy available.”

The most accurate way to calculate your basal metabolic rate is to go to a lab and hook yourself up to a metabolic cart.

Fortunately, though, there are mathematical equations that can predict its results with a fair amount of accuracy.

You can learn more about this here, but know that this macro calculator uses one of these formulas to approximate your BMR.

(Total Daily Energy Expenditure) TDEE

TDEE macronutrients

Total daily energy expenditure is exactly what it sounds like:

The total amount of energy you expend every 24 hours.

Your TDEE is comprised of your basal metabolic rate (BMR) plus additional energy burned through physical activity and processing the food you eat.

If determining that sounds like a huge headache, don’t worry.

You don’t have to track every step you take, record readouts on cardio machines (they’re inaccurate anyway), approximate energy burned in weightlifting workouts, or try to estimate how much energy is burned through processing the food you eat.

Instead, you can just multiply your BMR based on your general activity level.

It’s not going to be 100% accurate, of course, but it doesn’t need to be.

Instead, it will give you a good starting point for determining your total daily energy expenditure (and thus how many calories you should eat), and then you can adjust your calories up or down based on how your body actually responds.

You can learn more about TDEE and how this calculator determines it here.

Now, if all this is new to you, I have two simple recommendations:

  • If you want to lose fat, I recommend you eat 75 to 80% of your TDEE.

This will be a large enough calorie deficit to drive fat loss but not so large as to cause problems.

  • If you want to gain muscle, I recommend you eat 110% of your TDEE.

A calorie surplus is crucial to maximizing muscle growth, but a large surplus is counter-productive.

As you’ll see, these recommendations are built into the calculator as presets.

Setting Up Your Macros

macronutrients calculator

Once you know your BMR, TDEE, and target caloric intake based on your goals, you’re ready to work out your macros.

And that’s what the bottom portion of the calculator is for.

As you’ll see, once you set your protein intake, it remains locked.

This makes it easy to adjust carbs and fats up and down using either the sliders or input fields.

If You Want to Maximize Fat Loss

macronutrients for weight loss

If your goal is rapid fat loss, I have a few tips for you:

  • Set your protein intake to 1 to 1.2 grams per pound of body weight.

If you’re very overweight (a man with 25%+ body fat or a woman with 30%+), I recommend you set your protein intake at 40% of your total calories.

  • If you exercise regularly and don’t have any medical conditions, set your fat intake to 0.2 to 0.25 grams per pound of body weight.

This gives your body what it needs for basic health purposes and leaves plenty of calories for carbs.

  • Allot the rest of your calories to carbs.

Trust me.

Eating a lot of carbs does not make you fat (overeating does) nor does it hinder fat loss (overeating does).

Keeping your carb intake high is going to help you in many ways: better workouts, better meal plans, better mood and energy levels, and more.

Experience it for yourself and you’ll never look back.

  • If you’re sedentary, though, or have a medical condition like diabetes, then you’ll probably do better with fewer carbs.

If you’re sedentary, about 25% of daily calories from carbohydrate should be plenty.

If you have a relevant medical condition, check with your doctor as to your “carbohydrate ceiling.”

I’ve seen a lot of variation here.

If You Want to Maximize Muscle Growth

macronutrients for muscle building

If your goal is maximum muscle growth, then you’ll want to set your macros up a little differently.

Before we get to that, though, you should also know that you only want to “bulk” if your body fat percentage is in the right range.

For guys, this is about 10%. For girls, about 20%.

You can learn more about why here.

With that in place, here’s how I recommend you set up your bulking diet:

  • Set your protein to 1 gram per pound of body weight.

You don’t need more than this.

  • Set your fat to 0.3 to 0.4 grams per pound of body weight.

This leaves a large amount of calories for your carbs.

  • Get the rest of your calories from carbs.

This high-carb approach is going to help you build muscle faster in several ways.

The Bottom Line on Macronutrient Calculators

macro calculator

Many people find counting and tracking just calories burdensome enough.

The thought of keeping tabs on three different quantities sounds insufferable.

It’s really not, though. With a little “practice” it just becomes second nature.

And, more importantly, the payoff is huge:

  • You get to eat foods you actually like.
  • You improve body composition.
  • You don’t have to battle with overwhelming hunger or cravings.
  • You don’t have to cross your fingers and hope that it will work.

So, even if you’re still skeptical, give it a go. Follow the advice in this article and within a couple of weeks you’ll see real results in the mirror and on the scale.


What do you think about this macronutrient calculator? Have anything else to share? Let me know in the comments below!

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