What Are Macros? How to Calculate Your Macronutrients

Once you know your calorie target, the next step for many people is learning how to calculate macros, short for macronutrients: protein, carbohydrates, and fat. Calories tell you how much to eat, but macros tell you what those calories should be made of, which affects muscle, energy, and how full you feel. The maths is simple once you know that each gram of protein and carbohydrate provides 4 calories, while each gram of fat provides 9. This guide shows you how to turn a calorie target and a chosen split into gram targets, with a full worked example. To find your calorie number first, use our calorie calculator, then apply the steps below.

What are macros?

Macros, or macronutrients, are the three nutrients your body needs in large amounts and that supply energy: protein, carbohydrate, and fat. Protein builds and repairs tissue, carbohydrates are your main fuel, and fat supports hormones and absorbs certain vitamins.

Tracking macros means hitting target amounts of each, not just a calorie total. Two 2,000-calorie diets can look very different: one high in protein and one high in sugar will affect your body in different ways.

Calories per gram of each macro

The whole calculation rests on how many calories each gram provides:

Macronutrient	Calories per gram
Protein	4
Carbohydrate	4
Fat	9

Because fat is more than twice as calorie-dense as protein or carbs, a small change in fat grams shifts your calories quickly. Keep these three numbers in mind and the rest is arithmetic.

How to calculate your macros

1. Start with your daily calorie target.
2. Choose a percentage split across protein, carbs, and fat that adds up to 100%.
3. Multiply your calories by each percentage to get the calories from that macro.
4. Divide by the calories per gram (4 for protein and carbs, 9 for fat) to get grams.

A worked example

Suppose your target is 2,000 calories a day and you choose a balanced 40% carbs, 30% protein, 30% fat split.

1. Carbs: 40% of 2,000 = 800 cal, divided by 4 = 200 g.
2. Protein: 30% of 2,000 = 600 cal, divided by 4 = 150 g.
3. Fat: 30% of 2,000 = 600 cal, divided by 9 = about 67 g.

In plain English: on 2,000 calories with that split, aim for roughly 200 g carbs, 150 g protein, and 67 g fat each day. As a check, 200×4 + 150×4 + 67×9 comes to about 2,003 calories, which matches your target.

Get your calorie base first

Macros are built on your calorie target, so start there. Our calorie calculator gives your daily number, and our protein guide helps you set a sensible protein target before filling in carbs and fat.

Choosing a macro split

There is no single correct split; it depends on your goal:

• Balanced (40/30/30): carbs/protein/fat, a solid general-purpose starting point.
• Higher protein: useful when building muscle or losing fat, often 30 to 40% protein. Set protein first, at roughly 1.6 to 2.2 grams per kilogram of body weight, then split the rest.
• Higher carb: favoured by endurance athletes who need more fuel.

A common practical method is to fix protein by body weight, set fat at around 25 to 30% of calories, and let carbohydrates fill whatever calories remain.

Frequently asked questions

How do I calculate my macros?

Start with your daily calorie target, pick a percentage split for protein, carbs, and fat, then convert each to grams. Multiply your calories by each percentage, then divide by the calories per gram: 4 for protein and carbs, 9 for fat. On 2,000 calories with a 40/30/30 split, that is roughly 200 g carbs, 150 g protein, and 67 g fat.

What is a good macro split?

A balanced 40% carbs, 30% protein, 30% fat split works well for most people as a starting point. If you are building muscle or losing fat, a higher-protein split of 30 to 40% protein helps. Endurance athletes often prefer more carbohydrate. Adjust based on your goal, energy levels, and results over a few weeks.

How many calories are in a gram of protein, carbs, and fat?

Protein and carbohydrate each provide about 4 calories per gram, while fat provides about 9 calories per gram. These figures are the basis of every macro calculation. Alcohol, though not a macronutrient people usually track for nutrition, provides about 7 calories per gram if you need to account for it.

Should I count macros or just calories?

Calories determine weight change, so counting them alone can work for weight goals. But macros affect body composition, energy, and hunger. Tracking protein especially helps preserve muscle when losing weight and supports muscle gain. Many people count calories first, then focus on hitting a protein target, and worry less about exact carb and fat grams.

How much protein should my macros include?

A common guideline is 1.6 to 2.2 grams of protein per kilogram of body weight for people who are active or trying to build muscle, and slightly less for general health. Set your protein target first in grams, convert it to calories at 4 per gram, then divide the remaining calories between carbs and fat.

The bottom line

To calculate your macros, take your calorie target, choose a split such as 40% carbs, 30% protein, 30% fat, and convert each slice to grams using 4 calories per gram for protein and carbs and 9 for fat. On 2,000 calories that is about 200 g carbs, 150 g protein, and 67 g fat. Set protein by body weight for the best results, then fill in the rest. Start by finding your calorie base with our calorie calculator.

Further reading

For authoritative background on this topic, see Nutrient on Wikipedia.