Macros (macronutrients) are the three main nutrients your body needs in large amounts: protein, carbohydrates, and fat. Each provides energy (calories/kilojoules) and plays different roles in your body.

How much protein do I need?

For weight loss, aim for 1.6-2.2g of protein per kg of body weight to preserve muscle mass. For maintenance, 1.2-1.6g/kg is sufficient. For muscle gain, target 1.6-2.2g/kg.

Should I track macros or just calories?

Tracking macros gives you more control over body composition than tracking calories alone. Two diets with the same calories but different macro splits can produce very different results in terms of muscle retention and fat loss.

What macro split is best for weight loss?

A higher protein split (around 40% protein, 30% carbs, 30% fat) is generally recommended for weight loss as it helps preserve muscle mass, increases satiety, and has a higher thermic effect than carbs or fat.

Macro Calculator

This Macro Calculator works out your ideal daily intake of protein, carbohydrates, and fat based on your body stats, activity level, and goal. Whether you want to lose weight, maintain, or build muscle, get a personalised macro split in grams and percentages.

Enter Your Details

Gender

Age

years

Weight

Height

Activity Level

Goal

How It Works

Your macros are calculated in three steps: first, your Basal Metabolic Rate (BMR) is estimated using the Mifflin-St Jeor equation. Then your Total Daily Energy Expenditure (TDEE) is calculated by multiplying BMR by an activity factor. Finally, your calorie target is adjusted for your goal and split into protein (4 kcal/g), carbs (4 kcal/g), and fat (9 kcal/g).

Quick Reference

Goal	Calorie Adjustment	Protein	Carbs	Fat
Fat Loss	−20% deficit	40%	30%	30%
Maintenance	No change	30%	40%	30%
Muscle Gain	+10% surplus	30%	45%	25%

Percentages refer to the proportion of total daily calories from each macronutrient.

Frequently Asked Questions

What are macros?: Macros (macronutrients) are the three main nutrients your body needs in large amounts: protein, carbohydrates, and fat. Each provides energy (calories/kilojoules) and plays different roles in your body.
How much protein do I need?: For weight loss, aim for 1.6-2.2g of protein per kg of body weight to preserve muscle mass. For maintenance, 1.2-1.6g/kg is sufficient. For muscle gain, target 1.6-2.2g/kg.
Should I track macros or just calories?: Tracking macros gives you more control over body composition than tracking calories alone. Two diets with the same calories but different macro splits can produce very different results in terms of muscle retention and fat loss.
What macro split is best for weight loss?: A higher protein split (around 40% protein, 30% carbs, 30% fat) is generally recommended for weight loss as it helps preserve muscle mass, increases satiety, and has a higher thermic effect than carbs or fat.

How This Is Calculated

BMR (men) = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) + 5 BMR (women) = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) − 161 TDEE = BMR × activity multiplier Target Calories = TDEE × goal adjustment Protein (g) = (Target Calories × protein%) ÷ 4 Carbs (g) = (Target Calories × carbs%) ÷ 4 Fat (g) = (Target Calories × fat%) ÷ 9

BMR: = Basal Metabolic Rate - calories burned at complete rest
TDEE: = Total Daily Energy Expenditure - calories burned including activity
4 kcal/g: = Energy per gram of protein and carbohydrates
9 kcal/g: = Energy per gram of fat

Uses the Mifflin-St Jeor equation (1990), which is considered the most accurate predictive equation for estimating BMR in healthy adults. Activity multipliers range from 1.2 (sedentary) to 1.9 (very active).

Related Tools

Protein Intake Calculator

Calculate your daily protein needs based on body weight, activity level, and fitness goal. Includes Australian dietary guidelines.

TDEE Calculator

Calculate your Total Daily Energy Expenditure using the Mifflin-St Jeor equation. See how many calories and kilojoules you burn per day.

Keto Macro Calculator

Calculate your ideal fat, protein, and carb intake for a ketogenic diet. Customise net carb limits and protein targets.

Disclaimer

This calculator provides estimates for informational purposes only and should not be considered medical advice. Individual results may vary based on factors not captured by these formulas. Consult a healthcare professional before making changes to your diet or exercise routine, especially if you have any existing health conditions.