Macro Calculator
Calculate daily protein, carbohydrate, and fat targets in grams from your calorie goal and macro percentage split.
Inputs
Results
Macronutrients
Macronutrients ("macros") are the three nutrients that provide dietary energy:
| Macronutrient | Calories per gram |
|---|---|
| Protein | 4 kcal/g |
| Carbohydrates | 4 kcal/g |
| Fat | 9 kcal/g |
Tracking macros gives more precise control over body composition than counting calories alone, because the same calorie total with different macro ratios produces different effects on muscle retention, satiety, and hormones.
Calculation
Each macronutrient supplies a fixed amount of energy per gram, so a percentage of total calories converts directly to a mass in grams. Given a daily calorie target and percentage split:
The three percentages must sum to exactly 100% because all dietary calories come from these three sources.
The calorie target
A macro split divides a calorie total that has already been set; it does not set that total. The starting point is total daily energy expenditure (TDEE) — maintenance calories estimated from weight, height, age, and activity level. The calorie target is then derived from maintenance:
- Weight loss: subtract 300–500 kcal from maintenance
- Muscle building: add 200–400 kcal to maintenance
- Maintenance: use the maintenance figure directly
Common macro splits
| Goal | Protein | Carbs | Fat |
|---|---|---|---|
| General health | 20–25% | 50–55% | 25–30% |
| Weight loss | 30–35% | 40–45% | 25–30% |
| Muscle building | 25–35% | 45–55% | 20–30% |
| Low-carb | 25–35% | 25–35% | 35–45% |
| Ketogenic | 20–25% | 5–10% | 65–75% |
These are starting points rather than fixed prescriptions. Individual response varies, and the split is commonly adjusted based on observed results.
Worked example
A 75 kg person building muscle on a 2 500 kcal/day target uses a 30/45/25 split:
- Protein: 2 500 × 0.30 ÷ 4 = 187.5 g/day
- Carbohydrates: 2 500 × 0.45 ÷ 4 = 281.3 g/day
- Fat: 2 500 × 0.25 ÷ 9 = 69.4 g/day
At 1.6–2.2 g/kg for muscle gain, this person needs 120–165 g of protein daily, so the 187.5 g target falls comfortably in range.
Application and limits
Gram targets are a starting point rather than a rigid prescription. A common approach is to follow a set of targets for 2–4 weeks and then adjust based on energy, recovery, and progress toward the goal. When muscle gain stalls, protein is increased slightly or the calorie target is raised by 100–150 kcal; when fat loss stalls, carbohydrates or fat are reduced by about 5% each and the result monitored for another two weeks. Macro targets are estimates, and individual needs depend on metabolism, activity, health conditions, and goals — a registered dietitian or physician can advise on major dietary changes.
Frequently Asked Questions (FAQ)
What are macronutrients?
Macronutrients ("macros") are the three main categories of nutrients that provide calories: protein, carbohydrates, and fat. Protein and carbohydrates each provide 4 kcal per gram; fat provides 9 kcal per gram. Tracking macros gives more control over body composition than tracking calories alone, because equal calorie deficits with different macro splits produce different muscle retention and satiety outcomes.
Why does fat have more calories per gram than protein or carbs?
Fat molecules are more energy-dense because they are largely composed of carbon-hydrogen bonds, which store more chemical energy than the carbon-oxygen bonds dominant in carbohydrates. Fat yields 9 kcal/g vs. 4 kcal/g for protein and carbs. Alcohol, though not a macronutrient, yields 7 kcal/g.
Is there an ideal macro split?
No universal split fits everyone. Dietary guidelines typically suggest 45–65% carbohydrates, 10–35% protein, and 20–35% fat. For muscle building, higher protein (25–35%) is well-supported. For ketogenic diets, fat is raised to 65–75% with carbs below 10%. The most effective split is generally the one that is sustainable over time and supports the individual's goals and health.
Why must protein + carbs + fat equal 100%?
Because all dietary calories come from these three macronutrients (ignoring alcohol). If the three percentages summed to less than 100%, some calories would be unaccounted for; if more than 100%, the math would be internally inconsistent. The total must reach exactly 100% for the gram values to be valid.
How much protein is needed per day?
Research consistently supports 1.6–2.2 g per kg of body weight per day for muscle building and retention, especially in a calorie deficit. For a 70 kg person, that works out to 112–154 g/day. The 30% protein split at 2000 kcal gives 150 g, a reasonable target for most active adults.
Is it better to track by grams or by percentages?
Once gram targets are set, tracking in grams is more precise and practical. Food labels report in grams, and kitchen scales measure in grams. The percentage split is a starting point for calculating those gram targets.
Disclaimer
Macro targets are estimates based on the calorie totals and percentages you enter. Individual needs vary with metabolism, activity level, health conditions, and goals. Consult a registered dietitian or physician before making major dietary changes.
Recommended Next
TDEE Calculator
Estimate total daily energy expenditure (TDEE) and a macronutrient split (protein, fat, carbs) from body metrics, activity level, and a calorie goal.