Calculate your daily macronutrient targets — protein, carbohydrates, and fat — based on TDEE and your body composition goals.
A macro calculator works out how many grams of protein, carbohydrates and fat you should eat each day. It starts from your daily calorie needs (TDEE), then splits those calories into the three macronutrients based on your goal — such as weight loss, muscle gain or maintenance. Protein and carbs provide 4 calories per gram, and fat provides 9.
| Macro | Grams | Calories | % |
|---|
Calculating macros is a three-step process: find your calories, set your protein, then divide the rest between carbs and fat.
There is no single "correct" macro ratio — the best split depends on your goal. These are common evidence-based starting points.
| Goal | Protein | Carbs | Fat |
|---|---|---|---|
| Balanced / maintenance | 30% | 40% | 30% |
| Weight loss (higher protein) | 40% | 30% | 30% |
| Muscle gain | 30% | 45% | 25% |
| Low-carb | 35% | 20% | 45% |
| Keto | 25% | 5% | 70% |
| Endurance athlete | 25% | 55% | 20% |
They answer different questions. A calorie calculator tells you how much to eat; a macro calculator tells you what those calories should be made of.
| Feature | Calorie Calculator | Macro Calculator |
|---|---|---|
| Tells you | Total daily calories | Grams of protein, carbs, fat |
| Best for | Overall energy balance | Body composition and performance |
| Detail level | One number | Three targets |
IIFYM — "If It Fits Your Macros" — is a flexible approach where you hit your daily protein, carb and fat targets without banning specific foods. It works because body composition is driven mainly by total calories and macros, not by which exact foods provide them. In practice, most people still build meals around whole foods for fibre, vitamins and fullness, then use their remaining macros flexibly.
The NHMRC Acceptable Macronutrient Distribution Ranges (AMDRs) for adults: Protein 15–25%; Carbohydrates 45–65%; Fat 20–35%. Requirements change based on activity level and body composition goals.
Macronutrients (macros) are the three primary categories of nutrients that provide calories: protein, carbohydrates, and fat. Every food contains some combination of these three. Understanding your macro targets lets you optimise your diet for specific goals — fat loss, muscle gain, endurance performance, or general health — rather than just counting total calories.
| Macronutrient | Calories per gram | Primary Function | Daily Reference Value (DRV) |
|---|---|---|---|
| Protein | 4 cal/g (17 kJ/g) | Muscle repair, enzymes, satiety | 50g (general reference) |
| Carbohydrates | 4 cal/g (17 kJ/g) | Primary energy, brain fuel | 310g |
| Fat | 9 cal/g (37 kJ/g) | Hormones, vitamins, cell membranes | 70g |
| Alcohol (not a macro) | 7 cal/g | No nutritional value | — |
| Goal | Protein | Carbohydrates | Fat |
|---|---|---|---|
| General health (sedentary) | 15–20% | 45–55% | 25–35% |
| Fat loss | 30–35% | 35–45% | 25–30% |
| Muscle gain | 25–30% | 45–55% | 20–25% |
| Endurance athlete | 15–20% | 55–65% | 20–25% |
| Low-carb / ketogenic | 20–30% | 5–10% | 60–75% |
Target: 2,000 calories/day (500 cal deficit). Split: 35% protein, 40% carbs, 25% fat:
What are macros and why do they matter?
Macronutrients — protein, carbohydrates, and fat — are the three energy-providing nutrients in food. Total calories determine whether you gain or lose weight; the macro split determines body composition (muscle vs fat) and how you feel. Two people eating 2,000 calories can have very different results depending on protein, carb, and fat ratios.
How much protein should I eat per day?
NHMRC recommends 0.75g/kg of bodyweight as a minimum for sedentary Australian adults. For muscle building, research supports 1.6-2.2g/kg. For fat loss while preserving muscle, 1.8-2.4g/kg is recommended. Older adults (50+) benefit from higher protein (1.2-1.6g/kg) to counteract sarcopenia. A 75kg person building muscle should aim for approximately 120-165g of protein per day.
Should I count macros or just calories?
Both approaches work for weight management. Calorie counting alone is simpler; macro tracking gives more control over body composition. For fat loss, high protein (30-35% of calories) significantly helps preserve muscle and increases satiety. For general health, hitting calorie targets with reasonable macro balance is sufficient. Athletes and serious trainees benefit most from precise macro tracking.
What is the best macro split for weight loss?
A higher-protein split (30-35% protein) with moderate carbs and fat produces the best fat loss results while preserving muscle. Example on 1,800 calories: 150-160g protein (35%), 155-180g carbs (40%), 50-60g fat (25%). Total calorie deficit matters most — macro splits influence body composition quality and satiety within the deficit.
How do I calculate my macros?
First find your daily calories (TDEE) adjusted for your goal. Set protein (often 25–40% of calories), then divide the rest between carbs and fat. Convert to grams using 4 calories per gram for protein and carbs, and 9 for fat. The calculator above does all of this instantly from your details.
What are the best macros for muscle gain?
A common muscle-gain split is around 30% protein, 45% carbs and 25% fat, eaten in a slight calorie surplus with strength training. Protein supplies building material and carbs fuel your workouts. Aim for roughly 1.6–2.2 g of protein per kg of body weight within that split.
What are the best macros for weight loss?
For fat loss, a higher-protein split — around 40% protein, 30% carbs, 30% fat — works well in a calorie deficit. The extra protein preserves muscle and controls hunger, while you still get enough carbs and fat for energy and hormones. Total calories remain the main driver of weight loss.
What is IIFYM or flexible dieting?
IIFYM stands for "If It Fits Your Macros." It means hitting your daily protein, carb and fat targets without labelling foods as off-limits. It gives flexibility while still driving results, because body composition depends mainly on total calories and macros. Most people still centre meals on whole foods for health.
What are the best macros for keto?
A ketogenic split is very high fat, moderate protein and very low carb — roughly 70% fat, 25% protein and 5% carbs. This keeps carbohydrate low enough for the body to rely on fat for fuel. Keto suits some people but is restrictive, so it is not necessary for most goals.
Do I need to hit my macros exactly?
No. Being within about 5–10 grams of each target daily is close enough for good results. Protein is the most worth prioritising; carbs and fat can flex a little day to day. Consistency over weeks matters far more than perfection on any single day.
Should I count calories or macros?
Macros include calories, so tracking macros automatically manages both. If you only want a simple start, counting calories is easier. If you care about body composition or performance, tracking macros gives more control over how those calories are split between protein, carbs and fat.