Macro Calculator

Calculate your daily macro targets (protein, carbs, fat) from your TDEE, activity level, goal, and diet style. See gram and calorie breakdown instantly.

What is Macro Calculator?

A macro calculator determines how many grams of protein, carbohydrates, and fat you should eat each day to reach a specific weight or fitness goal. Rather than just tracking total calories, macro tracking accounts for how those calories are composed — since protein, carbs, and fat each play different roles in muscle preservation, energy levels, and body composition.

The calculation starts with your Basal Metabolic Rate (BMR), the calories your body burns at rest, calculated from your weight, height, age, and sex using the widely validated Mifflin-St Jeor equation. This is then multiplied by an activity factor to estimate your Total Daily Energy Expenditure (TDEE) — the calories you burn in a typical day including exercise and movement.

From there, your TDEE is adjusted based on your goal (a deficit to lose weight, a surplus to gain weight, or no change to maintain), and the resulting target calories are split into protein, carbs, and fat according to your chosen diet style, whether that's a balanced approach, low-carb, high-protein, or ketogenic.

Formula

BMR (male) = 10 × weight(kg) + 6.25 × height(cm) - 5 × age + 5

BMR (female) = 10 × weight(kg) + 6.25 × height(cm) - 5 × age - 161

TDEE = BMR × Activity Multiplier

(Sedentary 1.2, Light 1.375, Moderate 1.55, Active 1.725, Very Active 1.9)

Target Calories = TDEE + Goal Adjustment

(Lose -500, Maintain 0, Gain +300)

Protein (g) = (Target Calories × Protein %) / 4

Carbs (g) = (Target Calories × Carb %) / 4

Fat (g) = (Target Calories × Fat %) / 9

How to Calculate

Enter your weight and height.
Enter your age and select your sex for the BMR calculation.
Select your activity level based on your typical weekly exercise.
Select your goal — lose, maintain, or gain weight.
Select a diet style to see your protein, carb, and fat targets in grams and calories.

Example

A 30-year-old male weighing 80kg at 180cm with a moderately active lifestyle has a BMR of about 1,780 calories and a TDEE of about 2,760 calories. Aiming to lose weight with a balanced diet style, his target calories become 2,260, split into roughly 170g protein, 226g carbs, and 75g fat per day.

Key Benefits

Get personalized protein, carb, and fat targets instead of generic calorie advice
Understand exactly how many grams to eat of each macronutrient per day
Compare how different diet styles (balanced, low-carb, keto) change your daily targets
Support muscle preservation during weight loss with an adequate protein target
Quickly recalculate targets whenever your weight, activity level, or goal changes

Common Mistakes to Avoid

Setting protein too low, which accelerates muscle loss during a calorie deficit
Choosing an extremely aggressive calorie deficit that isn't sustainable and triggers muscle loss and fatigue
Ignoring fiber and micronutrient quality while focusing only on hitting macro numbers
Not adjusting macros as body weight changes significantly over weeks or months
Following a keto or very low-carb split without a genuine reason, when a more moderate approach may be easier to sustain

Pro Tips

Prioritize hitting your protein target consistently — it's the macro most linked to muscle preservation and satiety.
Recalculate your macros every 4-6 weeks or after a significant weight change, since your BMR shifts as your body composition changes.
Choose a diet style you can realistically sustain long-term rather than the most extreme option, since consistency matters more than precision.
Use whole, minimally processed foods to hit your macros — the same gram targets can come from very different quality food sources.
Don't neglect fat intake even on higher-protein plans; healthy fats support hormone production and long-term health.

Key Terms Explained

BMR (Basal Metabolic Rate): The number of calories your body burns at complete rest to maintain basic bodily functions
TDEE (Total Daily Energy Expenditure): Your BMR multiplied by an activity factor, representing total daily calorie burn
Macronutrients: Protein, carbohydrates, and fat — the three nutrients that provide calories and structure a diet
Calorie Deficit: Eating fewer calories than your TDEE, resulting in weight loss over time
Calorie Surplus: Eating more calories than your TDEE, resulting in weight gain over time
Ketogenic Diet: A very low-carb, high-fat diet that shifts the body's primary fuel source from glucose to ketones

Common Use Cases

Gym-goers and bodybuilders structuring meal plans around specific protein, carb, and fat targets
People starting a weight-loss journey who want a science-based calorie and macro deficit
Individuals following a ketogenic or low-carb diet who need precise gram targets
Athletes in a bulking phase calculating a calorie surplus with adequate protein for muscle growth
Nutrition coaches and personal trainers quickly generating starting macro targets for clients

Frequently Asked Questions

What are macros?

Macros (macronutrients) are the three nutrients that provide calories: protein (4 calories per gram), carbohydrates (4 calories per gram), and fat (9 calories per gram). Tracking macros means monitoring not just total calories but the balance between these three, which affects muscle growth, energy levels, satiety, and body composition.

How do I calculate my macros?

First calculate your BMR (Basal Metabolic Rate) using the Mifflin-St Jeor formula, then multiply by an activity factor to get your TDEE (Total Daily Energy Expenditure). Adjust TDEE up or down based on your goal (lose, maintain, or gain weight), then split the target calories into protein, carbs, and fat percentages based on your chosen diet style.

What is a good macro split for weight loss?

A common and effective split for weight loss is 35-40% protein, 25-30% carbs, and 30-35% fat, since higher protein helps preserve muscle mass and increases satiety during a calorie deficit. However, any split that hits your protein target (around 1.6-2.2g per kg of body weight) and creates a moderate calorie deficit will work.

How much protein do I need per day?

Most active individuals benefit from 1.6-2.2 grams of protein per kilogram of body weight per day, especially when trying to build muscle or preserve it during weight loss. Sedentary individuals can maintain health with less, around 0.8-1.2g per kg, though higher protein intake generally supports better satiety and body composition.

What's the difference between BMR and TDEE?

BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest just to maintain basic functions like breathing and circulation. TDEE (Total Daily Energy Expenditure) is your BMR multiplied by an activity factor, representing the total calories you burn in a day including exercise and daily movement — this is the number used to set calorie and macro targets.

Are keto macros different from regular macros?

Yes. A ketogenic diet drastically restricts carbohydrates (typically under 5-10% of calories, or 20-50g per day) while increasing fat to 70-75% of calories, forcing the body to use fat and ketones for fuel instead of glucose. This is a much more extreme carb restriction than typical low-carb or balanced diets.