How to Calculate Your Macros: A Step-by-Step Guide
Calculate precise protein, carb, and fat targets from scratch using your TDEE, goal, and food preferences.
Step 1: Calculate Your TDEE
Your macro targets start with knowing your maintenance calories (TDEE). Use the Mifflin-St Jeor BMR formula multiplied by your activity factor. Example: 180 lb (82 kg), 5'10" (178 cm), 30-year-old man, moderately active: BMR = (10×82) + (6.25×178) − (5×30) + 5 = 1,907. TDEE = 1,907 × 1.55 = 2,956 cal/day.
Step 2: Set Your Calorie Target
- Fat loss: TDEE − 300 to 500 cal
- Maintenance: TDEE
- Muscle gain (lean bulk): TDEE + 200 to 300 cal
Step 3: Set Protein (Always First)
0.7–1.0g per pound of bodyweight. At 180 lbs: 126–180g protein. Use 150g as midpoint. Calories from protein: 150 × 4 = 600 cal.
Step 4: Set Fat (Minimum Floor)
Minimum 0.3–0.4g per pound of bodyweight to support hormonal health. At 180 lbs: minimum ~60g fat. Calories: 60 × 9 = 540 cal. You can allocate more to fat if you prefer fewer carbs.
Step 5: Fill Remaining Calories With Carbs
For our example at 2,450 cal target (fat loss): 2,450 − 600 (protein) − 540 (fat) = 1,310 remaining. Carbs: 1,310 ÷ 4 = 328g carbs.
Final macros: 150g protein / 60g fat / 328g carbs = 2,452 calories.
Adjusting Over Time
If weight isn't changing after 2 weeks, adjust calories by 100–150 in the appropriate direction. Protein stays constant; adjust carbs or fat based on preference. Recalculate every 10–15 lbs of weight change as your TDEE shifts.