Macro Calculator
With daily calories 2400 kcal, body weight 80 kg, macro comes to 180 g — protein. It is reached in 4 steps, the last of which is 2400 * 30 / 100 / 4, and each one is printed on the page with its numbers filled in. The formula is the one published by NIH Office of Dietary Supplements, not an approximation fitted to it.
Grams of protein, carbohydrate and fat from a calorie target and a diet split. With protein per kilogram, the number a split is judged on.
Formula and sources checked · How we check
Daily calories 2400 kcal, Split Balanced — 30 protein / 40 carb / 30 fat, Body weight 80 kg
180 g
Protein for the example below. Editing a field recomputes the calculator below; this figure holds the answer the page was loaded with.
It is written into the HTML rather than drawn by a script, so a search engine reading this page without running JavaScript still finds an answer.
- Protein
2400 * 30 / 100 / 4180 g- Carbohydrate
2400 * 40 / 100 / 4240 g- Fat
2400 * 30 / 100 / 980 g- Protein per kg of body weight
180 / 802.25 g/kg
Worked example
2,400 kcal on a balanced split is 180 g protein, 240 g carbohydrate and 80 g fat. That protein figure is 2.25 g per kg for an 80 kg person — comfortably above the 1.6 g/kg where muscle-retention benefits plateau.
How to work it out yourself
- 1.Start from a calorie target rather than from the macros. The split divides a total; it does not set one.
- 2.Choose the split by what you are doing, not by what is fashionable. Higher protein preserves lean mass in a deficit; higher carbohydrate supports hard training volume.
- 3.Check the protein-per-kilogram line. Between 1.6 and 2.2 g/kg is well supported for someone training; below 1.2 is where lean mass starts paying for the deficit.
The formula
- Protein
2400 * 30 / 100 / 4 - Carbohydrate
2400 * 40 / 100 / 4 - Fat
2400 * 30 / 100 / 9 - Protein per kg of body weight
180 / 80
Source: NIH Office of Dietary Supplements — protein and macronutrients, USDA Dietary Guidelines for Americans
Questions people actually ask
- Why are protein and carbs 4 kcal and fat 9?
- Atwater factors, the measured average energy yield per gram. Fat carries more than twice the energy of the other two, which is why fat percentage swings total grams far more than protein percentage does.
- Does the split actually matter?
- Far less than total calories and total protein. Controlled trials find little difference in fat loss between splits at matched calories and protein. Pick the one you can stick to — that is the variable that decides the outcome.
- How much protein is enough?
- About 1.6 g per kg of body weight is where added muscle retention flattens out in the meta-analyses; going to 2.2 g/kg does little more except during aggressive deficits. Below roughly 1.2 g/kg, weight loss starts taking lean mass with it.
Related
- TDEE CalculatorHow many calories you burn in a day, from the Mifflin-St Jeor equation and an activity multiplier, with cut and bulk targets beside it.
- Calories Burned CalculatorEnergy burned by an activity from its MET value, body weight and duration. Net of what you would have burned sitting still, which trackers leave in.
- Protein CalculatorDaily protein from body weight, with the floor the DRI sets and the higher range the training literature uses, kept apart.
- Fat Intake CalculatorHow many grams of fat a day your calorie intake allows, inside the 20-35% range the Dietary Guidelines set, with the saturated fat ceiling separately.
- Calorie Needs CalculatorDaily calorie target for a weight goal, and the number it becomes after the first five, ten and fifteen pounds come off.
- Weight Loss Timeline CalculatorThe date you reach a goal weight at a given intake, with the deceleration the flat 3,500-calorie rule leaves out.
Part of a job
- Losing weight — 6 pages, in the order the questions arrive
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