Macro calculator

What are macros

Macronutrients ("macros") are the three main nutrients your body needs in large amounts: protein, carbohydrates and fat. Protein and carbs each provide 4 calories per gram, while fat provides 9 calories per gram. Together they make up your total daily calorie intake.

Getting the right balance of macros matters because each plays a different role. Protein supports muscle repair and growth, carbohydrates fuel your brain and workouts, and fat supports hormone production and overall health. This calculator helps you find a split that matches your body, activity level and goal.

How to calculate your macros

This calculator works in three steps:

• Step 1 — BMR: Your Basal Metabolic Rate is calculated using the Mifflin-St Jeor equation based on your age, gender, weight and height.
• Step 2 — TDEE: Your BMR is multiplied by an activity factor (from 1.2 for sedentary up to 1.9 for very active) to get your Total Daily Energy Expenditure.
• Step 3 — Calorie adjustment: Depending on your goal, the calculator adds or subtracts 500 calories from your TDEE. Lose weight gets a deficit, gain weight gets a surplus, and maintain uses your TDEE as-is.
• Step 4 — Macro split: Your calorie target is divided into protein, carbohydrate and fat grams based on your chosen diet preference. Balanced uses a 30/40/30 split, low-carb uses 25/20/55 and high-protein uses 40/30/30.

Adjusting for your goals

Your optimal macro split depends on what you are working toward:

• Weight loss: A calorie deficit of around 500 kcal below maintenance is a common starting point. A higher protein split (30–40%) can help preserve muscle mass while losing fat.
• Muscle gain: A surplus of around 500 kcal above maintenance, with adequate protein (30–40%) and enough carbs to fuel your training.
• Maintenance: Eat at your TDEE and adjust macros based on how you feel and perform. The balanced split works well for most people.

Remember that these are starting targets. Track your progress, how you feel and your energy levels, then adjust your intake by 100–200 calories at a time if needed.

Frequently asked questions

What are macronutrients?

Macronutrients are protein, carbohydrates and fat — the three nutrients that provide energy (calories). Protein and carbs provide 4 kcal/g, fat provides 9 kcal/g.

How many grams of protein do I need?

This depends on your weight, activity level and goal. Most adults need 0.8–2.2 g per kg of body weight. Sedentary individuals need about 0.8 g/kg, while active people benefit from 1.6–2.2 g/kg.

What's the best macro split for muscle gain?

A common starting split is 30% protein, 40% carbs and 30% fat with a ~500 kcal surplus. Adjust based on your training response and recovery.

Can I use this for weight loss?

Yes. Select the "Lose weight" goal and the calculator sets a deficit of 500 kcal below your TDEE. A higher protein split can help preserve muscle during a cut.

This tool provides estimates for informational purposes only. Consult a doctor or dietitian before making significant changes to your diet.