Free macro calculator
Your calories, split into protein, carbs and fat.
A calorie target tells you how much. Macros tell you what of. This works out both — your daily calories from the Mifflin–St Jeor equation, then protein, carbohydrate and fat in grams, across three splits. Free, no account, and nothing you type leaves your browser.
General wellness guidance, not medical advice. If you are pregnant, breastfeeding, under 18, or managing a medical condition — diabetes and kidney disease in particular, where protein and carbohydrate intake are clinical decisions — talk to a doctor or a registered dietitian first.
Percentages to grams, in one line
Macros are usually quoted as percentages of calories, but you eat grams. The conversion is just the energy density of each macronutrient:
| Macronutrient | kcal per gram | At 2,000 kcal, balanced split |
|---|---|---|
| Protein | 4 | 30% = 600 kcal = 150 g |
| Carbohydrate | 4 | 40% = 800 kcal = 200 g |
| Fat | 9 | 30% = 600 kcal = 67 g |
Fat looks small in grams for the same reason it is easy to overshoot: it carries more than twice the calories per gram. A tablespoon of oil is about 120 kcal.
Which split, and does it matter?
Less than the internet suggests. Calories decide whether your weight moves; protein decides how much of that movement is muscle rather than fat. Everything after that is preference and adherence — the best split is the one you will actually eat.
Balanced — 30 / 40 / 30
The default here and in the NutriLog AI app. Enough protein for most people, enough carbs to train on, enough fat for hormones and satiety. If you have no strong reason to pick another, pick this.
Higher protein — 40 / 30 / 30
The one worth switching to while you are losing weight. Protein is the most filling macro per calorie and the one that protects muscle in a deficit. The cost is that high-protein foods take more planning than carbs do.
Lower carb — 35 / 25 / 40
Useful if carbs leave you hungry an hour later, or if your day has no training in it. Not magic: at equal calories and equal protein, low-carb and higher-carb diets produce the same fat loss. Pick it because you prefer eating that way, not because you expect it to do more.
How much protein, in plain numbers
Roughly 1.6–2.2 g per kilo of body weight covers nearly everyone who trains, and the upper end is the useful one during a deficit. For a 70 kg person that is about 112–154 g a day. Below about 1.2 g per kilo you start shedding muscle along with the fat, which is the one outcome a weight-loss plan is supposed to avoid.
If the balanced split lands you under that, switch to higher protein rather than adding calories — the split moves grams around inside the same total.
Common questions
What is a good macro split for losing weight?
Higher protein, 40/30/30, for as long as you are in a deficit. It keeps you fuller per calorie and protects muscle. Then hit the calorie total consistently — that is still the part that decides the outcome.
Do I have to hit my macros exactly?
No. Within about 10 g on protein and fat, 20 g on carbs, is indistinguishable in results. A week that averages out beats one perfect day.
What about fibre, sugar and saturated fat?
They sit inside the three macros rather than beside them — fibre and sugar are carbohydrate, saturated fat is fat. This calculator does not target them. The app tracks fibre and sugar per meal if you want that level of detail.
Should my macros change on rest days?
They can, but they do not have to. Cycling carbs down on rest days and up on training days is a real technique with a small effect and a real adherence cost. Get a month of consistent logging behind you before adding that complexity.
Hitting them is the hard part.
Knowing your macros takes twenty seconds. Hitting them every day is the work — which is what the app is for. NutriLog AI logs food by search, barcode or recipe, shows all three macros as rings against these targets, and re-refines the targets each time you log a weight. Free, no ads, Android.