Macro Calculator
Get your personalized daily protein, carb, and fat targets
What Are Macros and Why Do They Matter?
Macronutrients — protein, carbohydrates, and fat — are the three categories of nutrients that provide calories. Protein and carbs each provide 4 calories per gram. Fat provides 9 calories per gram. Your total calorie intake determines whether you gain, lose, or maintain weight. Your macro split determines body composition — the ratio of muscle to fat you carry at any given weight.
Two people eating 2,000 calories per day can have dramatically different results. Person A eats 40% carbs, 30% protein, 30% fat and lifts weights — they build muscle and maintain a lean physique. Person B eats 60% carbs, 15% protein, 25% fat and does not exercise — they lose muscle mass over time even at the same weight. Calories determine the direction of the scale. Macros determine what that weight is made of.
Protein: The Non-Negotiable Macro
If you track nothing else, track protein. Research consistently shows that adequate protein intake (0.7-1.0 grams per pound of body weight) preserves muscle during fat loss, supports muscle growth during a surplus, improves satiety (you feel full longer), and has a higher thermic effect (your body burns more calories digesting protein than carbs or fat). A 175-pound person should aim for 123-175 grams of protein per day regardless of other goals.
Setting Your Macros
For fat loss: higher protein (30-35% of calories), moderate carbs (35-40%), lower fat (25-30%). The high protein preserves muscle while the calorie deficit comes from reduced carbs and fat. For muscle gain: moderate protein (25-30%), higher carbs (40-50%), moderate fat (20-25%). The higher carbs fuel workouts and recovery. For maintenance: balanced at roughly 30/40/30 protein/carbs/fat, adjusted to personal preference and activity level.
How accurate is this calculator?
This uses the Mifflin-St Jeor equation, the most validated formula for estimating metabolic rate. It is accurate to within 10% for most people. Use the results as a starting point, track for 2-3 weeks, and adjust based on actual results — if you are losing weight too fast, add 200 calories; too slow, subtract 200.
Do I need to hit my macros exactly?
No. Aim for within 10% of each target. Hitting protein within 10g and keeping total calories within 100 is sufficient for consistent results. Obsessing over exact grams creates an unhealthy relationship with food that undermines long-term adherence.