Why the count starts from weight, not calories
Sports nutrition targets are a convention
No official standard sets how much a person who trains should eat. The figures on this page are sports nutrition practice: 1.6 g of protein per kilogram of weight to maintain, 2 to bulk, 2.2 on a cut. The page uses exactly these and says so plainly, rather than passing them off as a rule.
Grams first, then calories
Most calculators start from daily calories and split them into three parts. Here it is the other way round: grams per kilogram of weight come first, and calories are their sum at 4 / 9 / 4 kcal per gram. The difference is not cosmetic – muscle needs a specific amount of protein, not a percentage of someone's calorie total.
If you already have your own calorie figure and only need to split it into macros, there is a separate macro calculator. And if you need energy use by age and height – the calorie deficit calculator.
The goal moves protein and fat, volume moves carbs
The goal sets two rows out of three. On a cut protein is higher, because in a deficit the body breaks down muscle more readily, and fat is lower, but not below 0.8 g per kilogram – below that limit hormones start to drop.
Carbs do not depend on the goal at all. They depend on how many hours a week you actually train: from 3 g per kilogram at three hours to 9 at the volumes seen in endurance sports.
The type of training shifts only the fuel
An hour of running and an hour with a barbell use different amounts of glycogen, so endurance adds 20 percent to carbs and strength training takes off 10. Protein and fat are not affected: a longer workout does not change how much fat you need per kilogram of weight.
Grams are rounded to whole numbers
Kitchen scales do not show tenths of a gram, so the card does not show them either. Calories are rounded to tens for the same reason: the sum of three rounded figures should not pretend to be accurate to one.
The check is on the scales, not on the page
Any formula is a starting point. After two or three weeks you see the truth: on a bulk your weight should creep up by about 0.25–0.5 kg a week, on a cut it should go down no faster than 1% of body weight. If it does not move, the figure has to change, and it is usually carbs that change, because protein and fat are already at a working minimum here.
With kidney or liver disease, diabetes or pregnancy, daily protein needs are set by a doctor, and their figure always takes priority over this page.