# What is a Macro Calculator and Why is it Useful?
A [macro calculator](https://https://bellyproof.com/science/macronutrients-explained-protein-carbs-fat/) is a tool that helps you determine the right balance of the three main macronutrients — protein, carbohydrates, and fats — based on your body type, activity level, and fitness goals.
Instead of just [counting calories](https://https://bellyproof.com/science/macronutrients-explained-protein-carbs-fat/), a macro calculator shows you how those calories should be divided among protein, carbs, and fats to fuel your body effectively. This makes it a more precise and sustainable approach to dieting, whether your goal is fat loss, muscle gain, or maintenance.

# How Does a Macro Calculator Work?
1. Input Your Details
You provide basic information such as age, weight, height, gender, body fat percentage (if known), and activity level.
2. Calculate BMR and TDEE
BMR (Basal Metabolic Rate): The calories your body burns at rest.

TDEE (Total Daily Energy Expenditure): The calories you burn daily, including activity and exercise.

3. Set Your Goal
You choose whether you want to lose weight, gain weight, or maintain your current weight.
For fat loss → a calorie deficit.

For muscle gain → a calorie surplus.

For maintenance → balanced intake.

4. Distribute Calories Into Macros
Your total daily calories are split into three macronutrients:
Protein: ~20–35%

Fat: ~20–35%

Carbs: ~40–60% (the remaining calories)

Conversions:
1 gram protein = 4 calories

1 gram carbs = 4 calories

1 gram fat = 9 calories

Benefits of Using a Macro Calculator
Ensures a balanced intake of protein, carbs, and fats.

Prevents under- or over-eating of specific nutrients.

Supports sustainable fat loss or muscle gain.

Makes diet tracking easier and more personalized.

# Try the Macro Calculator on BellyProof
If you want to take control of your nutrition, a macro calculator is the perfect tool. On BellyProof, we not only explain how macronutrients work but also provide insights into how to balance them for better results.
Use our [Macro Calculator](https://https://bellyproof.com/science/macronutrients-explained-protein-carbs-fat/) to find out exactly how much protein, carbs, and fat you should eat each day for your goals.