🍽️ Macronutrient Calculator
Enter your daily calorie target and a protein/carb/fat percentage split to see how many grams of each macronutrient that works out to per day. Protein and carbs are 4 kcal/g, fat is 9 kcal/g. Not medical advice.
Percentages to calories to grams
Each percentage takes its share of the calorie target, and that share is divided by the Atwater factor for the macronutrient - 4, 4 and 9 kcal per gram:
protein g = kcal × protein% / 100 / 4
carb g = kcal × carb% / 100 / 4
fat g = kcal × fat% / 100 / 92200 kcal split 30/40/30 gives 660 kcal of protein (165 g), 880 kcal of carbs (220 g) and 660 kcal of fat (73 g). Fat looks small beside carbs because each gram carries more than twice the energy.
Setting the split
- A percentage is not a dose. 30% protein is 120 g at 1600 kcal and 225 g at 3000. For a fixed gram target, nudge the percentage until the protein row reads what you wanted.
- Fat and carbs are the flexible pair. Most people fix protein first - strength-training guidance commonly lands near 1.6 to 2.2 g per kg of bodyweight - then move the other two against each other.
- Alcohol is missing. At 7 kcal per gram it belongs to none of the three boxes, so drinks eat the total without appearing in a row.
Frequently asked questions
How many grams of protein is 30% of 2200 calories?
165 g. Thirty percent of 2200 is 660 kcal, and protein supplies 4 kcal per gram.
How many calories are in a gram of fat?
Nine, against four for protein and four for carbohydrate. That is why a 30% fat allowance buys far fewer grams than a 30% carb allowance.
What macro split should I use?
There is no single correct answer; 30/40/30 is only a common starting point. Set protein at a level you can hit consistently, then divide what is left between carbs and fat to suit how you train.