Macro Calculator

How to Use

Choose your units, sex, age, height, weight, and activity level, then pick a goal (lose, maintain, or gain) and a macro split. The calculator shows your daily calorie target and the grams of protein, carbs, and fat to aim for. Use those gram targets in a food-tracking app to hit your macros each day.

Why This Tool Is Useful

Hitting a calorie goal is half the battle; how you split those calories between protein, carbs, and fat affects energy, muscle retention, and how full you feel. This calculator does the math behind 'if it fits your macros' (IIFYM) so you get concrete gram targets instead of vague percentages. Note: results are general estimates for informational purposes, not medical or nutritional advice — consult a professional before making significant dietary changes.

What Are Macros?

Macronutrients — 'macros' — are the three nutrients that provide energy: protein, carbohydrates, and fat. Protein and carbs contain about 4 calories per gram; fat contains about 9. Tracking macros, not just total calories, helps ensure you get enough protein and the right balance for your goal.

How Your Macros Are Calculated

First the calculator estimates your daily calories: it computes your BMR with the Mifflin-St Jeor equation, multiplies by your activity level to get your TDEE, then adjusts for your goal (a 500-calorie deficit to lose, or surplus to gain).

It then splits those calories by your chosen percentages and converts each to grams — dividing protein and carb calories by 4, and fat calories by 9.

Choosing a Macro Split

There is no single 'best' split — it depends on your goal and preferences. A balanced 30/40/30 suits most people. Higher protein helps preserve muscle in a deficit and keeps you full. Low-carb and keto shift calories toward fat and suit those who prefer it or have specific goals.

Whatever the split, prioritize protein: roughly 1.6–2.2 g of protein per kg of body weight is a common target for active people and those losing weight.

Do Macros Matter More Than Calories?

For weight change, total calories are what matter most — a deficit means loss, a surplus means gain, regardless of the split. Macros matter for body composition and how you feel: enough protein protects muscle, while carbs and fat are largely a matter of performance and preference.

Tips for Hitting Your Macros

A few practical pointers:

• Build meals around a protein source first, then fill in carbs and fat.
• Use a tracking app and weigh foods at first to calibrate your eye.
• Hitting protein consistently matters more than perfectly nailing carbs and fat.
• Re-run the numbers if your weight changes by a few kilos or your activity shifts.

Common Macro Splits (% of calories)