What are macronutrients?

Macronutrients are the three main nutrient groups that provide energy: protein, fat and carbohydrates. Each plays essential roles in the body — protein builds and repairs tissue, fat supports hormones, and carbs fuel activity.

How are macros calculated?

First, your Total Daily Energy Expenditure (TDEE) is estimated using the Mifflin-St Jeor equation and an activity multiplier. Then calories are distributed between protein, fat and carbs based on your goal.

How many macros do I need to lose fat?

For fat loss, a moderate calorie deficit (300-500 kcal below TDEE) is recommended, prioritising protein (1.6-2.2 g/kg), keeping fat at 25-35%, and filling the rest with carbohydrates.

How much protein do I need per kg of body weight?

For general health, 1.2 g/kg is a good baseline. For muscle building or fat loss, aim for 1.6-2.2 g/kg. Athletes or people in a large deficit may benefit from up to 2.4 g/kg.

What is the minimum fat intake I should have?

Health organisations recommend at least 20-25% of total calories from fat, or roughly 0.6-1.0 g per kg of body weight. Going below this can affect hormone production and nutrient absorption.

Do macros change with activity level?

Yes. More activity increases your TDEE, which raises total calories and therefore the absolute grams of each macro. The percentage split may also shift — more active people often benefit from higher carbohydrate intake.

Should I track macros for muscle gain?

Tracking macros can help ensure you eat enough protein and calories to support muscle growth. A small calorie surplus (200-300 kcal above TDEE) with 1.6-2.2 g/kg protein is a common approach.

Macro Calculator

Enter your details to get a personalised macronutrient plan. Our calculator uses science-backed formulas to estimate your energy expenditure and distribute protein, fat and carbohydrates based on your goal.

Sex

Age

years

Height

Weight

Activity Level

Goal

How We Calculate

Our calculator uses the Mifflin-St Jeor equation to estimate your Basal Metabolic Rate (BMR), then applies an activity multiplier to determine your Total Daily Energy Expenditure (TDEE). Macronutrients are distributed based on evidence-backed guidelines: protein is set according to body weight and goal, fat is kept within healthy minimums, and carbohydrates fill the remaining calories. The algorithm enforces safety limits including calorie floors and maximum deficit caps.

FAQ

Related Calculators

Calorie Calculator

Find out your Total Daily Energy Expenditure (TDEE) and how many calories you need to maintain, lose or gain weight.

Calorie Deficit Calculator

Calculate the right calorie deficit for safe, sustainable weight loss and get your recommended macros.