Macro Calculator

Carbohydrates, protein and fat are categorized as macronutrients, i.e., the most abundant nutrients in our daily diet. They provide energy and maintain normal bodily structure and functions.

To stay healthy and at a moderate weight, tracking your daily calories and macros is crucial, which you can do via a free macro calculator.

About You

How Active Are You?


About You

How Active Are You?


This post elaborates on macronutrients, their pros and cons, and how they impact your body weight. We then explain what a macronutrient calculator is, how it works out your daily requirement of macros based on age, sex, weight, and activity, and how a free macro calculator can help you attain ideal body weight with a flexible dieting plan.

What Are Macronutrients?

Macronutrients are compounds that we eat in large quantities and largely determine our body weight. They comprise proteins, carbohydrates and lipids, and are the primary energy sources, thus essential to carry out normal functions.

Therefore, tracking macros concerning how many calories you need in a day is essential.

Other nutritional substances, like vitamins, minerals, water, iodine, etc., are micronutrients.


Proteins are organic compounds made of small blocks of molecules called amino acids. They are present in all cells and tissues of the body but are especially concentrated in skin, hair, bones, muscles and nails.

Twenty different amino acids have been discovered. These molecules arrange themselves in specific patterns and sequences, forming a chain, which is then called protein. Over 10,000 different proteins have been identified.

Out of these 20, 11 are synthesized naturally in the body. These are called non-essential amino acids:

  • Alanine
  • Arginine
  • Asparagine
  • Aspartic acid
  • Cysteine
  • Glutamic acid
  • Glutamine
  • Glycine
  • Proline
  • Serine
  • Tyrosine

The rest of the nine amino acids are not made in the body and, therefore, must be consumed in the diet. These are:

  • Histidine
  • Isoleucine
  • Leucine
  • Lysine
  • Methionine
  • Phenylalanine
  • Threonine
  • Tryptophan
  • Valine


The following are the main sources of proteins:

  • Meat
  • Eggs
  • Fish
  • Poultry
  • Legumes
  • Fruits
  • Vegetables
  • Nuts
  • Seeds
  • Soy products

It is necessary to mention that animal-based, processed foods are a more dependable source of complete protein because plant products often lack some amino acids.

Daily Dietary Requirement

The daily dietary allowance for proteins in an average adult is 0.8 grams for each kg of body weight. For example, a person weighing 120 kg needs 96 grams of protein daily.

Food (100 grams)

Protein (grams)

Beef Meat


Poultry (chicken breast)




Soy milk


Legumes (raw pinto beans)


Note that this value is generic, and while it can prevent deficiency, several other factors like lifestyle, activity level, BMI, and age factor in when deciding if protein intake is optimal.

Effect On Weight

Consuming protein-rich food is associated with steady weight loss and muscle gain. Protein boosts satiety hormones which reduces hunger, thus helping in losing fat and weight.

However, you should know that when you eat more protein than required, the surplus amount is stored as fats, which can adversely lead to significant weight gain. Therefore, keeping a balance and tracking appropriate protein consumption by using a macro calculator is important.


Here’s why our bodies need proteins:

Help Gain Muscle and with Growth

Protein ensures the provision of essential amino acids which support growth and muscle gain. Science has, by and again, proven a strong correlation between development in childhood and protein intake.

The research found that consumption of a diet rich in animal protein at one year of age was associated with better height and BMI until nine years of age. Due to this, experts recommend feeding meat and poultry to infants early on in life.

Similarly, protein intake also affects the progression of puberty, and appropriate protein content in the diet must be ensured in growing children and young adults.

Hormone and Enzyme Synthesis

Enzymes are substances formed in our bodies that act as catalysts for biochemical reactions. This means that enzymes regulate the metabolism and make sure it is carried out at a healthy rate.

Hormones are chemicals that act as messengers in the body, that travel in the blood, and signal specific organs to carry out different tasks. They are important for various critical functions like blood pressure regulation, sexual function, reproduction, mood and appetite regulation.

All enzymes and most hormones (except corticosteroids and sex hormones) are made of proteins.

Cell Structure and Tissue Stiffness

Proteins provide structure to the cell. Structural proteins are an important component of the cytoskeleton and help form and maintain it.

Keratin, a protein, forms hair, nails, and the outermost layer of skin. It supports these tissues, repairs and heals them in case of damage, and keeps them healthy.

Similarly, another protein called elastin provides elasticity and strength to the skin, keeping the signs of ageing at bay.

Collagen, an incomplete protein (missing an amino acid), is also a major component of muscles, bones, and skin.

pH Maintenance

Hemoglobin is a blood protein that forms red blood cells. It binds and transports inhaled oxygen throughout the body and carries carbon dioxide to be eliminated from the lungs.

Hemoglobin amino acids are also capable of binding to acids and thus help maintain the body pH at an optimum level, i.e.,7.4.

Electrolyte Balance

A protein synthesized in the liver, called albumin, is critical to maintaining osmolarity, fluid and electrolyte balance in the body. This means that low concentrations of albumin in the blood can correspond with low calcium and sodium.

Improves Immune System

Dietary proteins enhance cellular immune systems, especially T-cell function. T-cells initiate an antigen-specific attack and are, therefore, highly crucial for protection against foreign bodies and pathogens.

Stores and Transports Micronutrients

Special transport proteins carry substances in and out of the cell and throughout the bloodstream. They are required for the transport of vitamins and minerals.

Prevents Blood Loss

Proteins called clotting factors help in platelet aggregation at the site of damage to blood vessels. This mechanism is called clotting and is highly crucial to prevent blood loss.


Sugar, starch, and cellulose are all made of 2:1 hydrogen and oxygen and are grouped together as organic compounds called carbohydrates or carbs.

When several small, simple sugars or monosaccharides (glucose, fructose, galactose, xylose, and ribose) and their derivatives join together, they form a carbohydrate.

For example:

  • Glucose and fructose combine to form sucrose (a type of sugar)
  • Amylose and amylopectin, polymers (long chain) of differently structured glucose, join together to form starch
  • Glucose monomers (single glucose molecules) form cellulose


The main natural sources of carbohydrates are:

  • Unprocessed /lightly cooked whole grains
  • Vegetables (ex: potato, black-eyed peas, green peas, carrot, butternut squash, etc.)
  • Fruits (ex: dates, resins, apples, berries, etc.)
  • Beans (ex: kidney beans, lima beans, pinto beans, etc.)
  • White rice
  • Corn
  • Milk
  • Almond butter

Note that these are natural and healthy whole foods, but carbs are also concentrated in several junks and packaged goods like soft drinks, spaghetti, potato chips, etc.

Daily Dietary Requirement

General dietary guidelines suggest that carbs should make up 45 to 65% of the number of calories you need daily. Generally, daily intake of 2000 calories for women and 2500 for men are advised. Knowing 1 gm of carbs is broken down into four calories, your daily carb intake should be 350 grams on average.

Know that this goes for sugar and starch because cellulose cannot be metabolized in the body.

Food (100 grams)

Carbohydrates (grams)



Fruit (apples)


Whole grains


Beans (raw pinto beans)


White rice




Effect On Weight

Excess carbohydrates are stored as fat, which is why consuming a carb-rich diet can contribute to weight gain. Therefore, if gaining muscle is the goal, it is crucial to use a macro calculator to check how many carbs you need.

However, this does not stand for cellulose, which cannot be digested due to a lack of appropriate enzymes. Cellulose makes you feel fuller without adding calories, which induces satiety and helps you lose weight.


Carbohydrates are the main source of energy in the body. Their key functions are:

Provide Energy and help gain weight

Each gram of carbohydrate contributes four calories of energy. Glucose is an immediate source of energy, which is why glucose solutions are often given to athletes and visibly lethargic people.

One of the best things about carbs is that when in excess, they can be stored in the body as glycogen, which is later converted into fats. This comes in handy when the body is calorie deficit, but the food is not readily available.

Carbs are also crucial for muscle growth, and help gain weight.

Treats Constipation

While sugar and starch are broken down during digestion, dietary cellulose (fiber) cannot be metabolized in the body.

When consumed, this fiber passes through the GIT without breaking down. On its way, it absorbs water and, consequently, forms a gel-like, bulky substance. This makes the stool bulky and also applies pressure on the intestinal walls, the combination of which eases constipation.

This holds true for both soluble and insoluble cellulose; however, the latter is a better laxative.

Heart Health

Healthy carbohydrates sourced from healthy food like whole grains and cereals decrease the risk of chronic heart disease (CHD) by 10 to 20%.

Dietary fiber intake (cellulose) also reduces the risk of plaque formation in cardiac arteries (arteriosclerosis) by reducing inflammation. Additionally, they also keep you feeling full without getting digested, which helps control your appetite and aids in weight loss.

However, it is crucial to note that these effects have limitations. For example, refined carbs (sourced from fizzy drinks and other forms of junk foods, can increase the risk of developing several heart diseases.

Similarly, consuming excessive carbs such as sugar or starch can lead to unhealthy weight gain.

Cognitive Development

The brain requires more energy than any other organ of the body. Since carbohydrates are readily available and can easily be broken down into calories, they are crucial for brain functions.

Several studies have been carried out over the years that prove carbohydrates play a critical role in cognitive development. The research found that carbs consumption improves memory and concentration.

Therefore, not having adequate carbs in diet can be detrimental to cognitive health.

Lipid Metabolism

Lipid metabolism is carried out via a process called Krebs’ cycle. Carbohydrates act as a substrate for Krebs’ cycle and, by extension, help regulate lipid metabolism.

Fats are crucial for various body functions, which is why ensuring optimal carbohydrate intake is essential.

Prevents Ketosis

Ketone bodies are compounds produced from fat metabolism. In periods of fasting, or when carbohydrate levels are insufficient, the body makes up for it by breaking down fat reserves into ketone bodies.

While ketone acts as an alternative energy source, it also induces several health complications like fatigue, dizziness, nausea, muscle soreness, and irritability.

This increased concentration of ketones is called ketosis.

Adequate consumption of carbs prevent ketone formation and, thus, ketosis.

Lipids (Fats)

Lipids are organic compounds made of fatty acids. They can be categorized as natural oils, waxes, and steroids.

Based on chemical bonding, fats are divided into saturated and unsaturated. The former category, also known as trans fats, tends to stay solid as body fat, which is why it can lead to fatty deposits in the vascular system.

Unsaturated fats, on the other hand, stay liquid at room temperature and do not pose a risk of atherosclerosis (arterial narrowing /complete blockage).


Dietary lipids primarily come in the form of oils like:

  • Canola
  • Corn
  • Olive
  • Safflower
  • Sunflower
  • Soy

They are also consumed as solid fats that come from:

  • Nuts
  • Seeds
  • Fish
  • Meat
  • Butter

Daily Dietary Requirements

A gram of body fat provides nine calories to the body. As per the general recommendation, daily intake of saturated fats should be limited to 30 g for men and 20 g for women.

Ideally, your total fat consumption on a 2000-calorie diet should be approximately amount to 400 to 700 calories (20 – 35%) of body fat. Of this quantity, 50 to 65% should be unsaturated fat. Olives, avocados, pumpkin seeds, canola oil and nuts are all sources of unsaturated fat.

The following table shows how many grams of fat are present in its food sources:

Food (100 grams)

Fat (grams)

Nuts (pistachio)




Avocado Oil


Fish (salmon, Atlantic)


Butter and margarine


Effect On Weight

Of an equivalent amount (in grams) of the three types of macros, fats contribute the most calories. In the case of low activity, high fat consumption can lead to high body fat percentage, unhealthy weight and obesity.


Here’s why body fat is important for the body:

Provide Energy

When you eat something containing fat, the fats are transported as is all the way to the intestine. In there, they are broken down into fatty acids and glycerol, which are eventually converted into energy.

Body fat also acts as an energy reserve. Excess carbs and proteins are converted into fats. Additionally, the fat not used directly upon eating is also stored.

When the body is depleted of energy and macros are not available for breakdown, this stored fat is used to keep the body running.

Absorption Of Vitamins

Vitamins A, D, E, and K are fat-soluble vitamins that cannot be absorbed in the body in the absence of fats.

These four vitamins are essential micronutrients required by the body to function normally.

  • Vitamin A or retinoic acid is crucial for vision, growth, fertility, and the immune system.
  • Vitamin D absorbs calcium and phosphorus, without which you are prone to weak bones, bleeding, mobility problems, CVDs, etc.
  • Vitamin D prevents free radical damage.
  • Vitamin K helps synthesize important proteins that we need for coagulation (blood clotting to prevent excessive blood loss)


Fats can help boost immunity. According to research, unsaturated fats enhance T-helper cell functions and increase antibody production, which helps prevent /reduce disease progression.

Evidence suggests that saturated fatty acids might also affect cellular immune responses.

Sexual Activity and Reproduction

Fats play a crucial role in sexual activity and reproduction. They are required to synthesize sex hormones (estrogen and testosterone). A low-fat diet is therefore associated with low libido.

Fats also help form prostaglandins which regulate the menstrual cycle, ovulation, and reproductive system. The same chemical also induces labor.

Cognitive Development

As we know, fats are broken down into fatty acids to be used as energy. Omega-3 and omega-6 are two crucial fatty acids that are essential for cognitive development and functions.

However, it is important to mention that a high-fat diet is also correlated with dementia and cognitive deficits in some. Therefore, it is important to ensure the consumption of foods specifically rich in omega-3 and omega-6. These include eggs, canola and coconut oil, fish, etc.


Omega-3, also known as docosahexaenoic acid (DHA), is crucial for retinal protection and integrity. Therefore, appropriate fat intake is critical for your visual function.

Macro Calculator

Now that we know about macronutrients let’s talk about macronutrient calculator.

We know that ensuring an appropriate consumption of calories matter. These are, simply put, calculators with a built-in equation that help calculate calories and macros. This, by extension ensures that your daily calorie intake is up to the mark.

Here are the things it takes into consideration:

  • Sex
  • Current weight and height
  • Age
  • Activity level
  • Weight goals (maintain /lose /gain weight)

Based on your input, the calculator generates your most accurate macros and daily calorie requirements compatible with your ideal weight.

What Affects Your Macros Requirement?

Here’s how the data asked by a macro calculator affects number of calories you require daily:

Sex and Body Composition

When it comes to calories and hence macronutrients, females need slightly fewer carbs, protein and fat in their diet than males. However, vitamin and mineral needs are higher in females.

This is because body composition differs between men and women. Women have more body fat percentage, whereas men have more muscle mass. Muscles require more energy than what is required to maintain fat.

Physiologically, men can burn fat more quickly (higher fat loss) because of higher lean muscle mass (because it consumes more calories). On the other hand, the fat tends to collect and stay in women for a longer time, and excessive fat intake on top of it can lead to obesity.  To balance the body fat percentage, calorie requirements, especially with respect to fats are different for the two sexes.

Current Weight and Height

Height and weight makeup BMI or body mass index. BMI readings correspond with four categories, i.e., underweight, normal, overweight, or obese. Your required calorie intake and hence macros consumption varies based on your current and normal /ideal healthy weight.


As we age, lean muscle mass gradually decreases, and the fat proportion increases. Consequently, your daily requirement for macros also changes.

Lifestyle Habits and Physical Activity Level

Activity level refers to a number that expresses your physical activity. Understandably, the more you engage in intense exercise like resistance training, the more calories you burn. Based on a high total daily energy expenditure, you naturally need more macros than other individuals.

Make sure to carefully select your macro calculator activity level, because there is often different classification for each free macro calculator.

Body Weight Goals

Macro calculator factors in your goal, i.e., whether you want to gain, lose or maintain weight when generating your daily calorie requirement. This can act as a weight loss calculator that helps you eat fewer calories, or a calculator that helps you with muscle gain.

Planning Diet To Gain or Lose Weight

Afterwards, the calculator allows you to plan your diet.

Macro calculator is widely used and preached for macro diet. There are several different diets used for weight loss (DASH, Keto, low fat, very low calorie, low carb diet etc.) and for if you want to gain gain (going all-in with more fat, potatoes, starches, milk, protein smoothies, etc.).

All of these meal plans rely on either completely restricting certain macros or taking all three of them excessively.  This can result in calorie deficit, and other side effects.

After discussing the importance of the three macronutrients, as well as their respective side effects when taken in high concentration, we know that incorporating proteins, carbs, and fats together and in balance is critical to stay healthy.

This is where IIFYM or If It Fit Your Macros comes in. Unlike other routines we mentioned earlier, IIFYM is a flexible dieting plan that believes that you can reach /stay at a healthy weight while eating anything you like, as long as you ensure optimal intake of the three macronutrients.

Ideally, here’s how macronutrient ratio should be in your diet (daily calorie requirement):

  • Proteins – 10% to 35%
  • Carbohydrates – 45% to 65%
  • Fats – 20% to 35%

In order to not gain weight, a lot of people tend to starve themselves, and the resultant calorie deficit can be life threatening. Body recomposition via IIFYM food intake ensures you meet your protein, carbohydrate, and fat needs that are compatible with your basal metabolic rate.

Similarly, if you want to gain muscle, you need to consume more calories than you require. The calculator gives you the most accurate macros for you and ensures your calorie surplus diet helps you reach your ideal weight.

Keeping in mind the content of proteins, carbs, and fats in each of their respective food sources, you can easily design a meal plan to your liking that also fulfils your daily calorie requirement generated by the macro calculator.

About The Author

Scroll to Top