Macro Calculator
Split your daily calories into protein, carbohydrate and fat targets in grams.
Your details
Moderate exercise 3–5 days a week
Within the National Academies' ranges
This is an estimate from a published formula, not medical advice. Individual results vary widely. Talk to a doctor or registered dietitian before making changes to your diet, training or medication.
This splits a daily calorie target into protein, carbohydrate and fat in grams.
Protein is set from body weight rather than as a percentage, which is the part that matters most.
How to set macros
Macronutrients are the three things that provide energy: protein at 4 calories per gram, carbohydrate at 4, and fat at 9. Total calories determine weight change; the split determines what that change is made of.
Most macro advice starts with percentages, such as 40/30/30. That is the wrong way round. A percentage of a calorie target is not a protein requirement. A 70 kg person needs about 126 g of protein whether they are eating 2,000 calories or 3,000, and that is 25% of one and 17% of the other.
The order that works: set protein from body weight, set a fat floor for hormonal function, and let carbohydrate take the remainder. Carbohydrate is the flexible one, and it should be, since it is what fuels training.
Protein and fat are set by physiology; carbohydrate absorbs whatever is left. Raise or lower the calorie target and only the carbohydrate figure needs to move much.
What to enter
- Daily calorie target
- From your TDEE adjusted for your goal. Everything is divided out of this.
- Body weight
- Sets protein and the fat floor. Percentages cannot do this job.
- Goal
- Cutting pushes protein higher to protect muscle. Bulking allows more carbohydrate to fuel training.
- Split preference
- Higher-carb or higher-fat, once protein and the fat floor are covered. This part is genuinely down to preference.
Where each target comes from
- [Protein](/health/protein-intake-calculator): 1.6-2.2 g/kg
- From resistance-training research. Higher end when cutting, to protect muscle.
- Fat: at least 0.5-0.8 g/kg
- A floor rather than a target. Going persistently below it affects hormonal function.
- Carbohydrate: the remainder
- Fuels training and recovery. The most flexible macro and the easiest to adjust.
- Fibre: 25-38 g
- Part of the carbohydrate total, and worth tracking separately for satiety and gut health.
- Alcohol: 7 cal/g
- Not a macro anyone needs, and it counts towards the total whether or not you log it.
What this assumes
Total calories drive weight change. The split affects body composition, hunger and training quality, not the direction of the scale.
Body-weight-based targets overestimate for people carrying substantial excess fat. Lean body mass or a target weight is the better basis there.
How to calculate your macronutrient targets
Three steps, in this order. Do not start with percentages.
- protein and fat
- Set from body weight, in grams
- carbs
- Whatever calories remain, divided by 4
Set protein from body weight. 1.6-2.2 g/kg, towards the top when cutting. At 70 kg and 1.8 g/kg that is 126 g, or 504 calories.
Set a fat floor. At least 0.5-0.8 g/kg. At 70 kg and 0.8 g/kg that is 56 g, or 504 calories.
Give the rest to carbohydrate. 2,000 − 504 − 504 = 992 calories, which at 4 per gram is 248 g.
Adjust carbohydrate as calories change. Protein and the fat floor stay put. Only the carbohydrate figure moves much when the target does.
See a worked example: why percentages mislead
- Person
- 70 kg
- Target
- 2,000 calories
Protein at 1.8 g/kg: 126 g, which is 25% of a 2,000-calorie diet.
The same 126 g on a 3,000-calorie diet is only 17%. Same requirement, very different percentage.
So a fixed 30% protein rule gives 150 g at 2,000 calories and 225 g at 3,000, and the second is more than anyone needs.
Set protein in grams from body weight and the problem disappears entirely.
126 g protein, 56 g fat, 248 g carbs
Frequently asked questions
There is no single best split, and asking the question that way is the problem. Set protein from body weight, keep fat above a floor, and let carbohydrate take the rest.
Beyond those constraints, higher-carb and higher-fat approaches both work. Pick whichever you can actually sustain, because adherence matters more than the ratio.
Calories determine how much weight you lose or gain. Macros affect what that weight is made of, plus hunger and training quality.
Two people in the same deficit with very different protein intakes lose different proportions of muscle and fat. That is the difference macros make.
Getting within about 5-10 g is fine for fat and carbohydrate. Protein is the one worth hitting more consistently, since it has the clearest dose-response.
Chasing exact numbers daily leads to a lot of stress for very little benefit. Weekly consistency is what shows up in results.
Not below roughly 0.5 g/kg sustained. Fat is needed for hormone production and to absorb the fat-soluble vitamins A, D, E and K.
Very low-fat diets tend to affect hormonal markers, mood and satiety. Treat the fat number as a floor, not a target to minimise.
No. Prioritising protein at each meal, eating mostly whole foods and controlling portions gets most of the benefit without any tracking.
Tracking is most useful as a short calibration exercise. A few weeks of it teaches you what portions actually contain, which is knowledge you keep afterwards.
Fibre is part of your carbohydrate total and worth tracking separately. 25-38 g a day helps satiety and gut health considerably.
Alcohol is 7 calories per gram and fits into no macro. It counts towards your total whether or not you log it, and it is one of the most common untracked sources.
Problems people actually run into
Setting protein as a percentage
A 30% protein rule gives 150 g at 2,000 calories and 225 g at 3,000, for a person whose actual requirement did not change.
Worse, in an aggressive deficit a percentage produces a protein target far too low for exactly the person who most needs it. Set grams from body weight instead.
Cutting fat to make room for carbohydrate
Fat has 9 calories per gram, so it is the obvious place to cut when calories are tight. Below about 0.5 g/kg that starts affecting hormonal function.
Take the calories from carbohydrate instead, or accept a smaller deficit. The fat floor exists for a physiological reason.
Results are estimates for general information only and are not professional financial, medical, or legal advice. Read our full disclaimer.
Last updated: September 4, 2026