🍎 Macro Calculator

Macronutrients ("macros") are the three nutrient classes the body needs in large amounts to fuel itself: protein, carbohydrates, and fat. Each gram of protein and carb supplies 4 calories; each gram of fat supplies 9 calories. Hitting daily macro targets helps balance energy, body composition, and athletic performance.

BMR (basal metabolic rate) is the energy your body burns at complete rest just to keep organs running. TDEE (total daily energy expenditure) is BMR multiplied by an activity factor — the total calories you burn in a typical day. Your daily calorie target is TDEE plus or minus a deficit/surplus to lose or gain weight.

Mifflin-St Jeor is the modern default and works well for most people using only age, sex, height, and weight. Katch-McArdle factors in lean body mass (via body fat %), so it tends to be more accurate for athletic or lean individuals who know their body fat percentage.

A balanced 30/40/30 (P/C/F) split works for most people aiming to maintain weight. Low-carb (40/25/35) and high-protein (40/30/30) splits are popular for fat loss or muscle building. Low-fat (25/60/15) suits endurance athletes. Choose a preset above or set your own — there is no single "best" ratio for everyone.

The formulas are widely accepted estimates from peer-reviewed nutrition science, but real-world energy expenditure varies by ±10–15% person-to-person depending on metabolism, genetics, NEAT (fidgeting), sleep, and stress. Use the result as a starting point and adjust up/down by 100–200 kcal per week based on how your body actually responds.

For safety, the calculator floors targets at 1500 kcal/day (male) and 1200 kcal/day (female) regardless of the goal you pick. Eating below these levels for extended periods can cause nutrient deficiencies and slow your metabolism. Aggressive cuts should be done under medical supervision.

No. This calculator is an educational tool only. If you have any health condition (diabetes, kidney disease, eating disorder, pregnancy, etc.), or are training competitively, please consult a registered dietitian, doctor, or qualified coach before changing your diet.