Macro Calculator
How it works
Each percentage is a share of the same calorie target: calories × pct / 100 gives that macro's calories. Grams are that figure divided by how many calories a gram of it holds — 4 for protein and carbohydrate, 9 for fat — which is why the same percentage produces noticeably fewer grams of fat than of protein or carbs.
The three percentages have to add up to 100%, since together they are meant to account for the whole calorie target. Picking a preset fills in one that already does; editing any of the three afterwards still recomputes live, so a preset is a starting point rather than a locked choice.
Frequently asked questions
Why does fat turn into fewer grams than protein at the same percentage?
Fat holds about 9 calories per gram, against 4 for protein and carbohydrate — energy density, not the size of the share. A 30% slice of the same calorie target is the same number of calories either way, but it takes more grams of protein or carbs to reach it than grams of fat.
Which split should I use?
It depends on the goal, not on any one formula: a 40/30/30 carb/protein/fat split is a common general-purpose starting point, lower-carb splits shift more of the target to fat and protein, and higher-protein splits are common when preserving muscle is the priority. This tool works out the grams for whatever split you enter — it does not pick one for you.
Where does the calorie number come from?
From somewhere else — this tool only splits a calorie target you already have into grams. The calorie calculator is a natural first step if you do not have a daily target yet.