📂 Health & Fitness ⏱ 6 min read 🗓 March 2026

How to Calculate Your Macros for Weight Loss or Muscle Gain

"Macros" is short for macronutrients: the three main components of food — protein, carbohydrates, and fat. Each provides energy (calories), but they have very different effects on your body, hormones, and body composition. Knowing your macro targets takes calorie counting from blunt to precise.

Step 1: Find Your Calorie Target

Before splitting calories into macros, you need a calorie target. This comes from your TDEE (Total Daily Energy Expenditure) adjusted for your goal:

Weight loss: TDEE minus 300–500 calories
Muscle gain: TDEE plus 200–300 calories
Maintenance / recomposition: At TDEE

Use the TDEE Calculator to find your maintenance calories first.

Get your personalised macro targets

Our Macro Calculator takes your TDEE, goal, and activity level and breaks your calories into specific protein, carbohydrate, and fat grams for the day.

Calculate Your Macros →

Step 2: Set Protein First

Protein is the most important macro for body composition, and the one most people undereat. It preserves muscle during weight loss, drives muscle growth during a surplus, keeps you full, and has the highest thermic effect (your body burns more calories digesting protein than carbs or fat).

Recommended protein intake:

Weight loss: 1.8–2.2g per kg of bodyweight
Muscle gain: 1.6–2.0g per kg of bodyweight
Sedentary maintenance: 1.2–1.6g per kg of bodyweight

For a 75kg person trying to lose weight, that's 135–165g of protein per day. Each gram of protein contains 4 calories, so 150g = 600 calories from protein.

Step 3: Set Fat

Fat is essential for hormone production, brain function, and absorbing fat-soluble vitamins. Don't go too low — extremely low-fat diets cause hormonal disruption and are hard to sustain.

Recommended fat intake: 20–35% of total calories. For a 2,000 calorie target, that's 44–78g of fat per day. Each gram of fat contains 9 calories.

Don't go below 0.6g per kg of bodyweight regardless of your calorie target.

Step 4: Fill the Rest with Carbohydrates

Once protein and fat are set, carbohydrates fill the remaining calorie budget. They're not essential in the way protein and fat are, but they fuel performance in the gym and provide fibre, micronutrients, and many people find them important for adherence and satiety.

Remaining calories ÷ 4 = daily carbohydrate grams (each gram of carbs = 4 calories).

Example calculation for a 75kg person targeting 2,000 calories for weight loss:
Protein: 150g × 4 = 600 calories
Fat: 65g × 9 = 585 calories
Carbs: (2000 − 600 − 585) ÷ 4 = 204g
Total: 600 + 585 + 816 = 2,001 calories ✓

Common Mistakes

Underestimating protein: Most people eat 60–80g/day and wonder why they lose muscle during weight loss. Hit your protein target first.
Being too rigid: Macros are a guide, not a prison. Hitting within 5–10g of your targets is fine. Obsessing over exact grams causes stress and disordered eating patterns.
Not adjusting for results: If you're not losing or gaining at the expected rate after 3–4 weeks, your TDEE estimate was off. Adjust calories by 100–150 and try again.
Ignoring fibre: Aim for 25–35g of dietary fibre daily. This isn't a separate macro target — it comes from your carbs — but it matters significantly for gut health and satiety.

Do You Have to Track Macros?

No. Many people achieve their goals by tracking calories alone, or simply following a consistent, high-protein diet without tracking anything. Macro tracking is a tool, not a requirement. It's most useful when progress has stalled despite tracking calories, or when you're trying to optimise performance alongside body composition.

Frequently Asked Questions

What are macros?

Macros (macronutrients) are the three main nutrient categories: protein, carbohydrates, and fat. Each provides calories — protein and carbs at 4 calories per gram, fat at 9. Tracking macros means hitting specific gram targets, not just a calorie total.

How do I calculate my macro targets?

First calculate your TDEE, then adjust for your goal (deficit for loss, surplus for gain). Set protein at 1.6–2.2g per kg of bodyweight, fat at 20–30% of calories, and fill the remaining calories with carbohydrates.

What macro split should I use for weight loss?

A commonly used split for weight loss is 30% protein, 35% carbs, 35% fat — though protein is the most important variable. Higher protein (30–35%) preserves muscle during a calorie deficit and keeps you fuller for longer.

What macro split is best for building muscle?

For muscle gain, aim for 1.6–2.2g protein per kg bodyweight, moderate fat (25–30% of calories), and the remainder from carbs. A slight calorie surplus of 10–15% above TDEE is generally recommended.

Do I need to track macros to lose weight?

No — calorie tracking alone is effective for weight loss. Macros become more important if you're training seriously, want to preserve muscle while losing fat, or have specific performance goals. For most people, hitting a calorie target with adequate protein is sufficient.