About the Macro Calculator
A macro calculator splits a daily calorie target into grams of protein, carbohydrate, and fat. Tracking macros rather than calories alone matters because the three deliver energy differently — protein preserves muscle, carbohydrate fuels hard training, and fat supports hormone production.
The formula
grams = calories · (percentage / 100) / kcal per gramProtein and carbohydrate provide 4 kcal per gram, fat provides 9. So 30 percent of a 2,200 calorie diet as protein is 660 kcal, or 165 g.
How to use this calculator
- 1Enter your Daily Calorie Goal (kcal). The field starts at
2200, which you can overwrite. - 2Enter your Protein % (25–35%). The field starts at
30, which you can overwrite. - 3Enter your Carbs % (40–50%). The field starts at
40, which you can overwrite. - 4Enter your Fat % (25–35%). The field starts at
30, which you can overwrite. - 5Read the result straight away — it recalculates as you type, so there is no button to press. Use Share to copy a link that reopens the page with your exact numbers filled in.
Worked example
| Input | Value |
|---|---|
| Daily Calorie Goal (kcal) | 2200 |
| Protein % (25–35%) | 30 |
| Carbs % (40–50%) | 40 |
| Fat % (25–35%) | 30 |
Result
Protein: 165 g/day (30%)
Carbohydrates: 220 g/day (40%)
Fat: 73 g/day (30%)
Total Calories: 2200 kcal
Those are the values the page loads with, so you can reproduce this result yourself and then change one field at a time to see what drives the outcome.
Understanding your result
Total calories determine whether you gain or lose weight; macro distribution determines what you gain or lose and how you feel doing it. In a deficit, adequate protein is what preserves lean mass, so a higher protein share is standard advice when cutting. Carbohydrate availability drives performance in high-intensity training, and fat below roughly 20 percent of intake risks disrupting hormone production.
Beyond meeting protein and fat minimums, the exact split matters less than adherence. Studies comparing low-carb and low-fat diets at matched calories and protein find little difference in fat loss. The right distribution is the one you can sustain and that supports your training.
Things worth knowing
- Set protein first at 1.6 to 2.2 g per kg of body weight, then fat at a minimum of 0.5 to 0.8 g per kg, and fill the remainder with carbohydrate.
- Percentages must total 100. A split that does not sum correctly will not match your calorie target.
- Higher protein increases satiety, which makes a deficit easier to sustain.
- Fibre is a carbohydrate but is largely unabsorbed. Aim for 25 to 35 g daily regardless of your split.
- Distributing protein across three or four meals supports muscle protein synthesis better than one large serving.
Frequently asked questions
What is a good macro split?+
A common starting point is 30 percent protein, 40 percent carbohydrate, and 30 percent fat. Endurance athletes usually go higher on carbohydrate; those on low-carb diets shift toward fat. Protein should stay adequate in all cases.
How much protein do I need?+
1.6 to 2.2 g per kg of body weight for anyone training, toward the upper end when in a calorie deficit. The general adult minimum of 0.8 g per kg is set to prevent deficiency, not to optimise body composition.
Do macros matter more than calories?+
Calories determine weight change; macros determine composition and performance. Both matter, but you cannot out-macro a calorie surplus if the goal is fat loss.
Should I eat fewer carbs to lose fat?+
Not necessarily. Studies matching calories and protein find little difference between low-carb and low-fat approaches. Choose the split you can adhere to and that supports your training.