Macro Calculator

How to Calculate Your Macros

Macros (macronutrients) — protein, carbohydrates, and fat — each contribute calories to your diet. Protein and carbohydrates provide about 4 calories per gram, while fat provides about 9 calories per gram. To calculate a macro target, your daily calories are divided according to the selected percentages, then each calorie target is converted into grams.

For example, if 2,000 calories are split 40% protein, 30% carbohydrates, and 30% fat, that gives 800 calories from protein, 600 from carbs, and 600 from fat. Dividing by 4, 4, and 9 respectively gives the corresponding gram targets.

These calculations use the standard energy values of approximately 4 kcal per gram for protein and carbohydrate and 9 kcal per gram for fat. The calculator is a planning tool, so actual food labels and dietary intake can vary slightly because of rounding and food composition.

Best Macro Splits by Goal

There is no single macro ratio that is optimal for everyone. These presets are practical starting examples rather than universal rules. Your appropriate protein, carbohydrate, and fat intake can vary with body size, training volume, calorie intake, dietary preferences, and health needs.

Cutting (Fat Loss)

This calculator uses 40% protein, 30% carbs, and 30% fat as a sample starting split. A higher-protein approach can be useful during a calorie deficit, while carbohydrate and fat intake can be adjusted around training demands and personal preference.

For a more individualized protein target, use our Protein Calculator. If you still need to determine your calorie target, our Calorie Deficit Calculator can estimate a starting calorie target for weight loss.

Maintenance / Balanced

This calculator uses 30% protein, 40% carbs, and 30% fat as a general example. There is no single required maintenance split. For context, the established adult Acceptable Macronutrient Distribution Ranges are 10–35% of calories from protein, 45–65% from carbohydrate, and 20–35% from fat. These reference ranges are not individualized training prescriptions.

Bulking (Muscle Gain)

This calculator uses 25% protein, 50% carbs, and 25% fat as a sample split. A calorie surplus combined with adequate protein and sufficient carbohydrate availability can support resistance-training performance and muscle gain.

If you are planning a muscle-gain diet, start with an appropriate calorie target and then adjust protein and the remaining calories between carbohydrates and fat based on your training and preferences.

Ketogenic

This calculator uses 25% protein, 5% carbs, and 70% fat as a simplified example. A ketogenic diet is generally characterized by very low carbohydrate intake, commonly around 20–50 grams per day or less than about 10% of calories. Individual carbohydrate thresholds for nutritional ketosis can vary, so a percentage split alone does not guarantee ketosis.

People with diabetes, people taking glucose-lowering medications, and anyone using a ketogenic diet for a medical purpose should discuss the approach with an appropriate healthcare professional before making major dietary changes.

Why Track Macros Instead of Just Calories?

Total calorie intake is central to changes in body weight, while macronutrients determine how those calories are distributed. Protein provides amino acids needed for tissue maintenance and repair, while carbohydrates and fat provide energy and contribute to other nutritional needs.

For people who train regularly, macro tracking can make it easier to monitor protein intake and adjust carbohydrate and fat intake around their calorie target.

Macro tracking is not required for everyone. Some people prefer to focus on total calories, protein intake, food quality, portions, or consistent eating habits instead of tracking every macronutrient.

Macro Calculator: What Should You Enter?

Enter the daily calorie target you actually want to use for your diet. If you are maintaining weight, this may be close to your estimated TDEE. For cutting or bulking, your target may be below or above estimated maintenance calories.

If you do not know your maintenance calories, use our TDEE Calculator first. For a more specific protein target, you can also use the Protein Calculator.

If your main goal is fat loss and you have not chosen a calorie target yet, use our Calorie Deficit Calculator to estimate a starting target before calculating your macros.

Macro Food Sources: What to Eat

Once you have your daily macro targets, choosing foods that fit those targets is the next step. Most whole foods provide a mix of macros, but they tend to be higher in one:

Protein sources

• Chicken breast, turkey, lean beef, pork loin
• Fish (salmon, tuna, cod), shrimp
• Eggs and egg whites
• Greek yogurt, cottage cheese, milk
• Tofu, tempeh, soy, lentils, beans
• Whey or plant-based protein powder

Carbohydrate sources

• Rice, oats, quinoa, whole-grain bread and pasta
• Potatoes, sweet potatoes, corn
• Fruit (bananas, berries, apples, oranges)
• Beans and legumes
• Vegetables (broccoli, spinach, peppers)

Fat sources

• Olive oil, avocado, nuts, seeds
• Fatty fish (salmon, mackerel, sardines)
• Nut butters
• Whole eggs and cheese (in moderation)
• Dark chocolate (in small amounts)

To plan protein alongside your other macros, see our Protein Calculator.

How to Adjust Your Macros Over Time

Macro targets are starting estimates, not permanent prescriptions. Most people need to adjust them based on how their body responds.

1. Follow your starting macro targets consistently for 2–3 weeks.
2. Track body-weight trend and, if possible, training performance.
3. If weight is not moving toward the goal, adjust calories by 100–200 kcal.
4. Keep protein relatively stable; adjust carbs and fat to match the new calorie target.
5. Reassess every 4–6 weeks.

For more on calorie adjustments during a cut, use our Calorie Deficit Calculator .

Frequently Asked Questions

Sources & Methodology

RepMaths uses established calorie-per-gram conversion factors for protein, carbohydrate, and fat. Goal presets are intentionally presented as starting examples rather than individualized medical or dietary prescriptions.

• U.S. Dietary Guidelines for Americans, 2025–2030
• U.S. and Canadian Dietary Reference Intakes: Macronutrients and Energy
• International Society of Sports Nutrition position stand on ketogenic diets

Calculator outputs are estimates for planning and education. They are not medical advice and should not be used to diagnose or treat a medical condition.