Calculateur de macronutriments

Macro Calculator

Hitting your daily calorie target is the first step toward weight management, but the split between protein, carbohydrates, and fat determines whether you lose fat or muscle, how your energy holds up during training, and how satisfied you feel after meals. This calculator converts your Total Daily Energy Expenditure (TDEE) into specific gram targets for each macronutrient based on your body weight, activity level, and goal — fat loss, maintenance, or muscle gain. The output gives you a concrete daily plan, not a vague ratio.

How Macros Are Calculated

The calculator first determines your TDEE using the Mifflin-St Jeor equation (see the TDEE calculator for the full formula), then adjusts total calories for your goal. Macros are then set in this priority order:

1. Protein — 4 calories per gram. Set at 0.7-1.0g per pound of body weight. Higher end (1.0g/lb) during a deficit to protect muscle; lower end (0.7g/lb) during maintenance or bulk.
2. Fat — 9 calories per gram. Minimum 0.3g per pound of body weight (roughly 50g/day floor) to support hormone production and fat-soluble vitamin absorption.
3. Carbohydrates — 4 calories per gram. Fills remaining calories after protein and fat are allocated. Carbs are the flexible macro and vary most between individuals.

The calorie adjustments by goal are: fat loss = TDEE minus 500 calories (targeting ~1 lb/week loss); maintenance = TDEE; muscle gain = TDEE plus 300-500 calories.

Worked Examples

Example 1 — Man cutting body fat. Jake is a 175-lb male with a TDEE of 2,600 calories. His fat loss target is 2,100 calories. Protein is set at 1.0g/lb = 175g (700 calories). Fat is set at 0.4g/lb = 70g (630 calories). Carbs fill the remaining 770 calories = 193g. His split works out to 33% protein, 37% carbs, 30% fat — a high-protein deficit that protects his muscle while creating a meaningful fat loss signal.

Example 2 — Woman maintaining weight with moderate activity. Leila is a 130-lb female with a TDEE of 1,950 calories. Protein is set at 0.75g/lb = 98g (392 calories). Fat is 0.35g/lb = 46g (414 calories). Carbs fill the remaining 1,144 calories = 286g. Her split is 20% protein, 59% carbs, 21% fat — appropriate for a moderately active woman not in a deficit, with plenty of carbs to fuel her workouts.

Example 3 — Man bulking for muscle gain. Carlos is a 165-lb male with a TDEE of 2,800 calories. His gain target is 3,100 calories. Protein stays at 0.8g/lb = 132g (528 cal). Fat is 0.4g/lb = 66g (594 cal). Carbs pick up the remaining 1,978 calories = 495g. His split is 17% protein, 64% carbs, 19% fat — carb-heavy to fuel high-volume training and support recovery.

Reference Table

When to Use This Calculator

• Starting a structured diet — translates your calorie target from the Calorie Calculator into daily gram targets you can actually track and build meals around
• Switching from casual dieting to body recomposition — once you know your calories, macro splits determine whether you preserve muscle during a cut or accumulate fat during a bulk
• Pre-contest or photo shoot prep — competitive athletes use precise macro targets to control body composition changes in the weeks before an event
• Optimizing training performance — if you are hitting your calories but still feel sluggish in the gym, the macro split may be the issue; this calculator helps you identify the imbalance
• Transitioning between diet phases — moving from a cut to maintenance or from maintenance to a bulk requires recalculating both calories and macro splits; use this calculator each time you change goals

Common Mistakes to Avoid

1. Skimping on protein during a deficit. This is the most expensive mistake in body composition. Eating too little protein while cutting turns a fat loss phase into a fat-and-muscle loss phase. Research consistently shows 0.8-1.0g of protein per pound of body weight is the threshold to preserve lean mass during a calorie deficit. When in doubt, go higher on protein and lower on carbs rather than reducing protein.

2. Letting fat drop too low. Fat provides 9 calories per gram, so it is tempting to cut it aggressively to save calories. But dropping below 0.3g per pound (or under 50g/day total) impairs testosterone production in men, disrupts menstrual function in women, and reduces absorption of vitamins A, D, E, and K. Keep fat at a minimum floor even during aggressive cuts.

3. Ignoring fiber within your carb allocation. Not all carbs function the same way. Getting all your carbs from refined sources like white bread and sugary foods will leave you hungry and cause energy crashes. Aim for at least 25-35g of dietary fiber per day within your carb total, primarily from vegetables, legumes, and whole grains.

4. Tracking macros without tracking for long enough. Two or three days of tracking tells you very little. You need at least 2-4 weeks of consistent data to see how your body responds to a given macro split. Changes in body weight, strength, and energy levels over that period tell you whether the numbers need adjusting.

Understanding Your Results

Your macro targets are shown in grams per day and as a percentage of total calories. The percentages are useful for comparison and sanity-checking — for fat loss, seeing protein at 30-40% of calories confirms you have set it high enough. But day-to-day, track in grams, not percentages, since the gram target stays fixed while the percentage shifts if your calorie intake varies.

Hitting your targets within 5-10 grams of each macro on most days is more than sufficient for results. Perfect tracking is not necessary — consistency over weeks matters far more than daily precision. If you miss your carb target by 20g on a rest day but nail your protein, that is fine.

Tips

1. Hit your protein target first each day — it is the most important macro for body composition and the hardest to accidentally overconsume
2. Spread protein across 3-5 meals with at least 25-40g per meal to maximize muscle protein synthesis throughout the day
3. Time carbs around workouts — consuming 30-60g of carbs in the 1-2 hours before or after training improves performance and recovery
4. Track using an app for at least 2-4 weeks to build an intuitive feel for portion sizes and macro composition of common foods
5. Recalculate every 4-6 weeks or whenever your body weight changes by more than 10 lbs, since protein and fat targets are weight-based
6. If you find the calculated carb amount too high or low for your preferences, swap calories between carbs and fat while keeping protein fixed