Macro Calculator
Turn daily calories into grams of protein, carbs and fat — balanced, low-carb, high-protein, keto or custom — with per-meal grams and a g/kg protein check.
Macro Calculator: with the default inputs, protein per day is 150.
Your target intake. Get it from the calorie calculator if you don't have one.
Used only to check protein in grams per kilogram.
grams
- Carbohydrate per day
- 175grams
- Fat per day
- 78grams
- Protein per kg body weight
- 21.6–2.2 g/kg is the evidence-based range for training adults.
- Protein per meal
- 50
- Carbs per meal
- 58
- Fat per meal
- 26
Assumptions
- Atwater factors: 4 kcal/g protein and carbohydrate, 9 kcal/g fat. Alcohol and fibre are not modelled.
- Presets are common conventions, not clinical prescriptions; several sit outside the AMDR on purpose.
- Per-meal figures divide the day evenly; you can bias protein toward post-training meals.
- Protein60030%
- Carbohydrate70035%
- Fat70035%
| Macronutrient | % of calories | Calories | Grams/day | Grams/meal |
|---|---|---|---|---|
| Protein | 30% | 600 | 150 | 50 |
| Carbohydrate | 35% | 700 | 175 | 58 |
| Fat | 35% | 700 | 78 | 26 |
Protein and carbohydrate supply 4 kcal per gram, fat 9 kcal per gram (Atwater factors).
| Style | Protein (g) | Carbs (g) | Fat (g) |
|---|---|---|---|
| Balanced | 150 | 175 | 78 |
| Low-carb | 200 | 100 | 89 |
| High-protein | 200 | 150 | 67 |
| Ketogenic | 125 | 25 | 156 |
How this is worked out
The formula
Protein (g) = calories × protein % ÷ 4 Carbohydrate (g) = calories × carb % ÷ 4 Fat (g) = calories × fat % ÷ 9 Presets (protein / carbs / fat): balanced 30/35/35 · low-carb 40/20/40 · high-protein 40/30/30 · keto 25/5/70
Open How it’s calculated above to see this worked through with your own numbers.
What you enter
- Daily calories
- Your target intake. Get it from the calorie calculator if you don't have one.from 500 to 10000 · defaults to 2000
- Diet style
- Choose one of 5 options.Balanced — 30% protein / 35% carbs / 35% fat · Low-carb — 40% protein / 20% carbs / 40% fat · High-protein — 40% protein / 30% carbs / 30% fat · Ketogenic — 25% protein / 5% carbs / 70% fat · Custom (set percentages under More options)
- Body weight
- Used only to check protein in grams per kilogram.in lb, kg, st · from 20 to 1000 · defaults to 165
- Meals per day
- A number.from 1 to 8 · whole numbers only · defaults to 3
- Protein(under More options)
- A number.a percentage · from 5 to 70 · defaults to 30
- Carbohydrate(under More options)
- A number.a percentage · from 0 to 80 · defaults to 40
- Fat(under More options)
- A number.a percentage · from 10 to 85 · defaults to 30
What you get back
- Protein per daymain answer
- grams
- Carbohydrate per day
- grams
- Fat per day
- grams
- Protein per kg body weight
- 1.6–2.2 g/kg is the evidence-based range for training adults.
- Protein per meal
- Carbs per meal
- Fat per meal
What this assumes
- Atwater factors: 4 kcal/g protein and carbohydrate, 9 kcal/g fat. Alcohol and fibre are not modelled.
- Presets are common conventions, not clinical prescriptions; several sit outside the AMDR on purpose.
- Per-meal figures divide the day evenly; you can bias protein toward post-training meals.
About this calculator
Once you know how many calories to eat, macros decide what those calories are made of. Protein, carbohydrate and fat each do different jobs, and the split changes how full you feel, how well you train and how much muscle you keep while dieting. This calculator turns a calorie target and a ratio into grams — the number you actually track.
How to use it
Enter your daily calories (the calorie calculator will give you one), pick a style, and add your body weight so the tool can sanity-check protein per kilogram. Set meals per day to see how the grams divide. Choose Custom and open More options to set your own percentages; they must total 100.
Choosing a split
- Balanced (30/35/35) is a moderate starting point that keeps protein high without cutting carbs hard.
- High-protein (40/30/30) suits fat-loss phases: protein is the most satiating macronutrient and has the highest thermic effect, and the research consensus (Morton et al. 2018) puts the muscle-protecting sweet spot around 1.6–2.2 g/kg.
- Low-carb (40/20/40) works for people who feel better with fewer carbs or who train lightly. It is not inherently better for fat loss at matched calories and protein.
- Keto (25/5/70) keeps carbs near 20–30 g so the body runs on ketones. It's a legitimate choice with real trade-offs for high-intensity training.
The reference ranges behind these numbers are the Acceptable Macronutrient Distribution Ranges from the US Dietary Reference Intakes: 10–35% protein, 45–65% carbohydrate, 20–35% fat. Several presets sit outside the AMDR deliberately; the calculator warns when fat drops below 20% or carbs below the 130 g RDA.
Protein first, then the rest
If you take one thing from this page: set protein by body weight, not by percentage. Percentages drift — 30% of 1,500 kcal is only 112 g. The protein-per-kg output tells you whether the split gives you enough at your calories. For most people who lift or are dieting, 1.6–2.2 g/kg is the target; sedentary adults are fine at the 0.8 g/kg RDA. Spreading protein across 3–5 meals of about 0.4 g/kg each maximises muscle protein synthesis.
What this can't do
Macros are a budget, not a food list. Fibre, micronutrients, food quality and consistency matter more than whether you hit 35% or 38% carbs. Hit protein, stay near your calories, and treat the carb–fat balance as personal preference.
Frequently asked questions
▸What are good macros for weight loss?
Keep protein at 1.6–2.2 g per kg of body weight, then split the remaining calories between carbs and fat however you eat most consistently. The high-protein preset (40/30/30) is a sensible default.
▸How many calories are in a gram of protein, carbs and fat?
4 kcal per gram of protein, 4 per gram of carbohydrate, 9 per gram of fat (and 7 per gram of alcohol). These Atwater factors are what the calculator uses.
▸Do I need to hit my macros exactly?
No. Within 5–10 g of protein and 10–15 g of carbs or fat on a given day is plenty. Weekly averages matter more than daily precision.
▸Why does the calculator warn that my protein is low?
Because a percentage-based split can leave protein well under 1.2 g/kg at lower calorie targets. Protein needs scale with body weight, not calories, so switch to a higher-protein preset or a custom split.
▸Is a low-carb or low-fat diet better?
At matched calories and protein, controlled trials find similar fat loss. Pick the one you can stick to. Very high-intensity training generally goes better with more carbs.
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Daily carbohydrate target in grams from your calories and diet split, with grams per meal, the IOM fibre target and the athlete g/kg bands for your training load.
Daily fat target in grams from your calories, with the saturated-fat ceiling, the omega-6 and omega-3 essential fatty acid minimums, and the IOM 20–35% range.