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Calculate daily protein, carbs, and fat grams from calories and macro ratio. Free macro split calculator for bodybuilding, keto, and balanced nutrition plans.
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Protein and carbohydrates each provide 4 kcal per gram. Fat provides 9 kcal per gram. Alcohol provides 7 kcal per gram. These factors are used by the FDA and EU for nutrition label calculation.
Calories = (Protein g × 4) + (Carbs g × 4) + (Fat g × 9) + (Alcohol g × 7)Enter macronutrient grams for one serving size. Total calories represent metabolizable energy available to the body, excluding indigestible fiber which contributes ~2 kcal/g but is often subtracted as insoluble fiber.
Net Carbs = Total Carbs − Fiber (optional for low-carb labeling)Fat-dominated foods exceed 400 kcal/100 g while lean protein and vegetables are under 150 kcal/100 g. Understanding macro composition explains why nuts (high fat) are calorie-dense despite small serving sizes.
Energy Density = Total Calories / Serving Weight (g) × 100Updated: July 2026
Standard 60 g sports nutrition bar with moderate macros.
→ 252 kcal (80 + 100 + 72)
Two slices whole grain bread with half avocado and toppings.
→ 334 kcal (32 + 140 + 162)
150 g skinless chicken breast, plain grilled without sauce.
→ 176 kcal (140 + 0 + 36)
Fat is 9 kcal/g — more than double protein and carbs. Underestimating fat grams is the most common error in homemade calorie calculations, especially for cooking oils and dressings.
Nutrition labels list total carbohydrate including fiber. For strict calorie counting, soluble fiber contributes ~2 kcal/g. Most Atwater calculations use total carbs × 4, which slightly overestimates high-fiber foods by 4–8 kcal per serving.
A tablespoon of olive oil adds 120 kcal (14 g fat) — often more than the protein source itself. Always include cooking oils, butter, dressings, and marinades in macro totals.
Food energy comes exclusively from protein, carbohydrates, fat, and alcohol — each with a defined caloric density. This calculator converts macronutrient grams per serving into total kilocalories using Atwater general factors used in nutrition labeling worldwide.