Macro Calculator

Free Fitness Tool

Estimate your daily protein, carbohydrate, and fat targets for weight loss, maintenance, or muscle gain. This macro calculator uses your body stats, activity level, and goal to create a simple starting point.

This calculator is for general education only. Macro needs vary by body composition, training, health status, and personal preference.
Estimated Daily Calories
--
calories per day
Enter Details

Add your details to estimate your daily macro targets.

--Protein
--Carbs
--Fat
--BMR
Protein--
Carbs--
Fat--

What Is a Macro Calculator?

A Macro Calculator estimates how much protein, carbohydrates, and fat you may want to eat each day. These three nutrients are called macronutrients because they provide energy and make up a large part of your diet.

Macro Calculator Formula

This calculator first estimates your BMR using age, gender, height, and weight. It then adjusts your calories using your activity level and goal. After that, it splits your calories into protein, carbs, and fat.

Step Formula
BMR Mifflin-St Jeor equation
Maintenance calories BMR × activity factor
Goal calories Deficit, maintenance, or surplus
Macros Calories split into protein, carbs, and fat

How to Calculate Macros

Protein and carbohydrates provide about 4 calories per gram. Fat provides about 9 calories per gram. That means a 2,000 calorie diet with 30% protein, 40% carbs, and 30% fat gives around 150g protein, 200g carbs, and 67g fat.

Macros for Weight Loss

For weight loss, this calculator uses a calorie deficit and a slightly higher protein percentage. Higher protein may help with fullness and muscle maintenance while dieting. Carbs and fats are then balanced around the remaining calories.

Macros for Maintenance

For maintenance, the calculator estimates calories close to your daily energy needs. This can be useful if you want stable weight, better food awareness, or a starting point before adjusting calories later.

Macros for Muscle Gain

For muscle gain, the calculator uses a calorie surplus and more carbohydrate availability to support training. Protein still matters, but carbs can help fuel workouts and recovery.

Protein vs Carbs vs Fat

Macro Main Role
Protein Supports muscle repair, fullness, and lean mass maintenance.
Carbohydrates Provide energy for training, daily activity, and performance.
Fat Supports hormones, cell structure, and absorption of fat-soluble vitamins.

Macro Calculator FAQ

Do I need to track macros forever?

No. Many people track macros temporarily to learn portion sizes and food balance.

Are macros more important than calories?

Calories control energy balance, while macros affect food quality, fullness, performance, and body composition.

Which macro is most important for weight loss?

Protein is often prioritized during weight loss because it can support fullness and muscle maintenance.

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