Loading Macro Split Calculator…
Optional. Used only to show grams per kilogram.
150 g · 300 g · 67 g
Protein, carbohydrate, then fat.
An estimate for training purposes and not medical advice. The split is arithmetic and it is exact; what it cannot tell you is whether the calorie target you fed it is right, or whether this division of it suits your body, your sport or your medical history. Anyone managing diabetes, kidney disease, an eating disorder or a pregnancy should take a macro target from a dietitian rather than from a ratio typed into a box.
Grams come from the Atwater general factors set out in FAO Food and Nutrition Paper 77: 4 kcal in a gram of protein, 4 in a gram of carbohydrate and 9 in a gram of fat. They are whole-diet averages rather than constants, so the gram counts are as precise as those three numbers and no more. All three sit inside the Institute of Medicine ranges for adults — protein 10–35%, carbohydrate 45–65% and fat 20–35% of energy.
A gram of protein carries about four kilocalories, a gram of carbohydrate about four, and a gram of fat about nine. Those three figures are the Atwater general factors, set out in section 3.5.1 of the Food and Agriculture Organization’s paper on food energy and conversion factors, and they are all this tool needs from the outside world. Everything else it does is division. Alcohol, at seven, is the fourth factor in that list and the one no macro plan has a column for.
Take 2,400 kilocalories a day divided 25 per cent protein, 50 carbohydrate and 25 fat. That is 600 kcal of protein, which at four per gram is 150 grams; 1,200 kcal of carbohydrate, or 300 grams; and 600 kcal of fat, which at nine per gram is only 67. Multiply those three gram counts back by four, four and nine and you land on 2,400 exactly, which is the one guarantee this page can honestly make.
Swap to 35 per cent protein, 25 carbohydrate and 40 fat at the same calories and you get 210, 150 and 107 grams. The protein rises by 40 per cent and the fat by 60 while the number of calories has not moved at all — which is the point of looking at grams rather than at percentages.
A split is a way of dividing a total. It cannot tell you whether the total is right, and getting the total wrong swamps any effect of how you carved it up. Nor does it know anything about food quality: 275 grams of carbohydrate from lentils and oats and 275 grams from confectionery are the same row on this page and very different days of eating. Fibre is counted inside the carbohydrate figure, as food labels count it, though a large part of it yields far less than four kilocalories per gram.
Every result is compared with the Acceptable Macronutrient Distribution Ranges from the Institute of Medicine’s 2005 reference intakes: 45 to 65 per cent of energy from carbohydrate, 20 to 35 from fat and 10 to 35 from protein. These are described in the source as ranges associated with reduced chronic disease risk while still supplying essential nutrients — not targets, and not limits. A split that falls outside one gets flagged rather than refused, because a great many people eat outside them on purpose and with good reason.
Yes, before rounding. The percentages are applied to the calories first and only then divided by four, four and nine, so the underlying figures reconcile to the penny. The displayed grams are rounded to whole numbers for readability, which can leave the visible sum a few kilocalories away from your target.
Because a gram of it carries more than twice the energy of a gram of the other two. A quarter of your calories from fat and half from carbohydrate can easily mean four times as many grams of carbohydrate on the plate. This is the single most common surprise people have when they first convert a percentage plan into food.
No. The flag means the split sits outside a population range published for chronic disease risk, which is a reason to have a reason rather than a warning to stop. Ketogenic and very high carbohydrate approaches both live outside those ranges by design, and both are used deliberately under supervision.
It supplies about seven kilocalories a gram and belongs in no macronutrient column, so a plan built here quietly ignores it. If drinking is a regular part of your week, subtract those calories from the daily target before splitting the remainder, otherwise the arithmetic on this page describes a day you did not actually have.