Enter your daily calorie target and pick a diet style to see exactly how many grams of protein, carbs, and fat you should eat each day, plus how many calories each macro contributes.
Protein150 g
Carbs200 g
Fat67 g
Protein calories600 kcal
Carb calories800 kcal
Fat calories600 kcal
How this calculation works
Each gram of protein and carbohydrate supplies about 4 calories, while each gram of fat supplies about 9 calories. Your chosen goal sets a percentage split of your total calories between the three macros (for example, balanced uses 40% carbs, 30% protein, 30% fat).
The calculator multiplies your daily calories by each macro's percentage to get that macro's calorie share, then divides by 4 (protein, carbs) or 9 (fat) to convert calories into grams.
Because the percentages always add to 100%, the three macro calorie totals always add back up to your original daily calorie target — this calculator just tells you how to divide those calories into food.
Worked example
At 2,000 calories on the balanced split (40% carbs / 30% protein / 30% fat): protein = 2,000 × 30% ÷ 4 = 150 g, carbs = 2,000 × 40% ÷ 4 = 200 g, and fat = 2,000 × 30% ÷ 9 ≈ 67 g. Protein and carbs each supply 600 calories, fat supplies 600 calories, totalling 2,000.
Calories per gram: the basis of every macro calculation
Protein — about 4 calories per gram; builds and repairs muscle, supports satiety and immune function.
Carbohydrate — about 4 calories per gram; the body's preferred fuel for the brain and high-intensity exercise.
Fat — about 9 calories per gram; supports hormone production, vitamin absorption, and long-duration energy.
The four diet-style presets
Each preset changes how your total calories are divided across the three macros, without changing your total calorie intake:
Diet style
Carbs
Protein
Fat
Typical use
Balanced
40%
30%
30%
General health, sustainable everyday eating
Low-carb
25%
40%
35%
Blood-sugar management, appetite control
High-protein
30%
40%
30%
Muscle building or preserving muscle in a cut
Keto
5%
30%
65%
Strict low-carb, fat-adapted metabolism
Tips for hitting your macro targets
Spread protein across 3–4 meals rather than one large serving, since the body uses dietary protein for muscle repair more efficiently when intake is distributed through the day. Lean meats, fish, eggs, dairy, tofu, and legumes are efficient protein sources.
Track your intake with a food-logging app for at least a week to see how close your normal eating already comes to the target — most people find one macro (often protein) is the one that needs the most deliberate adjustment.
Treat the gram numbers as a target range, not a rigid daily requirement. Being within 5–10 g of a macro target on a given day makes no meaningful difference to results.
Frequently asked questions
How do I know how many calories to eat?
Start from your maintenance calories (often estimated with a BMR/TDEE calculator), then subtract roughly 300–500 for gradual fat loss or add 200–300 for a lean muscle-gain surplus. Enter that adjusted number here to get your macro split.
Which goal preset should I choose?
Balanced (40/30/30) suits most people wanting a sustainable, general-purpose diet. Low-carb suits those managing blood sugar or preferring more fat/protein satiety. High-protein favors muscle retention during a cut or muscle gain during a bulk. Keto is a strict very-low-carb approach that shifts metabolism toward fat for fuel.
Why do protein and carbs use 4 calories per gram but fat uses 9?
This reflects each macronutrient's actual energy density, established by decades of calorimetry research (the Atwater system). Fat is more energy-dense than protein or carbohydrate, which is why high-fat diets pack more calories into less food volume.
Does this store my calorie target or diet goal?
No. Everything is calculated locally in your browser and nothing is uploaded, logged, or saved anywhere.
Is this the same as IIFYM ("If It Fits Your Macros")?
Yes, this calculator gives you the daily gram targets that IIFYM tracking is built around. You then log food throughout the day and try to hit those protein, carb, and fat totals rather than restricting specific foods.
Should alcohol or fiber count toward these macros?
Alcohol has its own calorie value (about 7 kcal/g) and isn't part of the three macros here, so heavy drinking will add calories this split doesn't account for. Fiber is technically a carbohydrate but many trackers subtract it from carb totals since it's not fully digested — check how your food-logging app handles it.
Do these percentages work for weight loss and muscle gain alike?
The percentage split only decides how your calories are divided, not whether you gain or lose weight — that depends on whether your total calories are above or below maintenance. Pick a split you can stick to, then adjust total calories for your goal.