How this calculator works
A percentage-only macro split can quietly lower protein when calories fall. This calculator starts with grams per kilogram: protein changes with the goal, while dietary fat receives a practical floor. Carbohydrate gets the remaining energy.
That structure reflects the different jobs of the macronutrients. Protein supports tissue repair, fat supplies essential fatty acids and helps absorb fat-soluble vitamins, while carbohydrate is the most adjustable lever and an important training fuel.
Protein and carbohydrate provide about 4 kcal per gram; fat provides about 9 kcal per gram. The tool sets protein and fat from body weight, then assigns remaining calories to carbohydrate.
How to use the result
The output is a planning range, not a requirement to land on every gram. Being close across a week is more useful than correcting dinner to hit a perfect pie chart. Food labels and portions already contain measurement error.
If the calorie target leaves almost no carbohydrate after protein and fat, revisit the calorie target. It usually makes more sense than driving an essential nutrient lower simply to make the arithmetic fit.
Get a more reliable result
Start with a calorie target that has already been tested against your weight trend. Enter body weight consistently and choose the goal that matches the next training block. The calculator protects a protein target and a practical fat floor first; carbohydrate is the adjustable remainder, so an unrealistic calorie target will produce an unrealistic split.
Common errors that change the answer
- Choosing percentages first and allowing protein to fall too low when calories decrease.
- Counting every gram as exact despite normal error in labels, recipes and portions.
- Changing macros repeatedly without first checking whether total calorie intake is consistent.
What to do next
- Anchor each main meal with a clear protein source.
- Spread fat across foods such as olive oil, nuts, dairy, eggs and fish.
- Place more carbohydrate around harder or longer training if it feels better.
Guides that support this calculator
Frequently asked questions
What macro split is best for fat loss?
There is no universal percentage. A sufficient protein range, a reasonable fat floor and a calorie intake you can sustain matter more than a fixed ratio.
Do carbs cause fat gain?
Body-fat gain reflects sustained energy surplus, not carbohydrate alone. Carbohydrate also supports high-intensity exercise and replenishes glycogen.
Must I hit macros exactly?
No. Aim for a repeatable range. Protein and total energy are usually the most useful numbers to make consistent.