How to Calculate Your Macronutrient Targets

What Macronutrients Are

Macronutrients are the three main categories of nutrients that provide calories: protein, carbohydrates, and fat. Each has a fixed caloric value per gram, established by the Atwater general factors used by the USDA and FDA:

• Protein: 4 calories per gram
• Carbohydrates: 4 calories per gram
• Fat: 9 calories per gram

Alcohol provides 7 calories per gram but is not a macronutrient because it is not essential for survival.

Standard Macro Ratio Guidelines

The Dietary Guidelines for Americans (2020–2025), published by the USDA and HHS, recommend the following Acceptable Macronutrient Distribution Ranges (AMDRs) for adults:

Protein Requirements by Goal

Protein targets vary significantly based on activity level and goals. The following are evidence-based ranges from sports nutrition research:

• Sedentary adults: 0.8 g per kg of body weight per day (the RDA set by the Institute of Medicine)
• Endurance athletes: 1.2–1.4 g/kg/day (International Society of Sports Nutrition)
• Strength/resistance training: 1.6–2.2 g/kg/day for muscle hypertrophy (meta-analysis, Morton et al., 2018, British Journal of Sports Medicine)
• Weight loss (preserving muscle): 1.8–2.7 g/kg/day of target body weight

How to Calculate Macro Grams from Percentages

Once you know your TDEE (total daily calorie target) and your desired macro percentages, converting to grams is straightforward:

1. Multiply TDEE by the percentage for each macro to get calories from that macro.
2. Divide by the calories-per-gram value (4 for protein and carbs, 9 for fat).

Example: 2,000 calorie target, 30% protein, 40% carbs, 30% fat:

• Protein: 2,000 × 0.30 = 600 ÷ 4 = 150g
• Carbs: 2,000 × 0.40 = 800 ÷ 4 = 200g
• Fat: 2,000 × 0.30 = 600 ÷ 9 = 67g