Health & Fitness
Macronutrients Calculator – Track Your Daily Nutrition
Calculate your daily protein, carbs, and fat needs with our free Macronutrients Calculator. Optimize your diet for weight loss, muscle gain, or fitness.
What Are Macronutrients?
Macronutrients are the three main nutrients your body needs in large amounts for energy, growth, and overall health: protein (4 cal/g), carbohydrates (4 cal/g), and fat (9 cal/g). Each plays a unique role — protein builds and repairs muscle, carbohydrates fuel your brain and muscles, and fats support hormone production and vitamin absorption.
This calculator uses the Mifflin-St Jeor equation to estimate your Basal Metabolic Rate (BMR), then multiplies it by your activity level to find your Total Daily Energy Expenditure (TDEE). Based on your goal and diet preference, it splits your calories into the optimal protein, carb, and fat ratios.
How to Use This Calculator
- Enter your weight, height, age, and gender
- Select your activity level — be honest for accurate results
- Choose your primary goal (weight loss, maintain, muscle gain, or recomposition)
- Pick a diet preference that matches your lifestyle
- Click "Calculate Macros" to get your daily protein, carb, and fat targets
Common Use Cases
- Fat loss: Get a calorie deficit with high protein to preserve muscle while losing body fat
- Muscle building: Find the right calorie surplus and protein intake to maximize muscle growth
- Body recomposition: Lose fat and gain muscle simultaneously with precise macro targets
- Meal prep planning: Use per-meal breakdown to portion meals for the week
- Diet comparison: Compare how keto, low carb, or balanced diets split your calories differently
- Athletic performance: Optimize fuel for training with the right carb-to-protein ratio
Diet Type Comparison
| Diet Type | Protein | Carbs | Fat | Best For |
|---|---|---|---|---|
| Balanced | 25% | 45% | 30% | General health, sustainable eating |
| Low Carb | 30% | 20% | 50% | Fat loss, blood sugar control |
| High Protein | 35% | 35% | 30% | Muscle building, athletic performance |
| Ketogenic | 25% | 5% | 70% | Rapid fat loss, epilepsy management |
| Low Fat | 25% | 60% | 15% | Heart health, endurance athletes |
Macronutrient Food Sources
🥩 Protein (4 cal/g)
| Chicken breast | 31g / 100g |
| Eggs (1 large) | 6g |
| Greek yogurt | 10g / 100g |
| Lentils (cooked) | 9g / 100g |
| Salmon | 25g / 100g |
🍞 Carbohydrates (4 cal/g)
| Brown rice (cooked) | 23g / 100g |
| Oats | 66g / 100g |
| Sweet potato | 20g / 100g |
| Banana (1 medium) | 27g |
| Whole wheat bread | 12g / slice |
🥑 Fats (9 cal/g)
| Avocado (1 medium) | 21g |
| Olive oil (1 tbsp) | 14g |
| Almonds (28g) | 14g |
| Peanut butter (2 tbsp) | 16g |
| Cheese (28g) | 9g |
Understanding BMR & TDEE
BMR (Basal Metabolic Rate)
The number of calories your body burns at complete rest just to maintain basic functions like breathing, circulation, and cell production. BMR accounts for about 60–75% of your total daily calorie burn.
Mifflin-St Jeor Formula:
Male: 88.362 + (13.397 × weight kg) + (4.799 × height cm) − (5.677 × age)
Female: 447.593 + (9.247 × weight kg) + (3.098 × height cm) − (4.330 × age)
TDEE (Total Daily Energy Expenditure)
Your total calories burned per day including all activity. Calculated as BMR × Activity Multiplier:
| Sedentary | BMR × 1.2 |
| Lightly active | BMR × 1.375 |
| Moderately active | BMR × 1.55 |
| Very active | BMR × 1.725 |
| Extremely active | BMR × 1.9 |
FAQ – Macronutrients Calculator
What are macronutrients and why do they matter?
Macronutrients are the three main nutrients your body needs in large quantities: protein, carbohydrates, and fat. They provide all the calories (energy) in your diet. Getting the right balance of macros supports your fitness goals, energy levels, body composition, and overall health.
How does this calculator determine my macro targets?
It first calculates your BMR using the Mifflin-St Jeor equation (based on weight, height, age, and gender), then multiplies by your activity level to get TDEE. Calories are adjusted for your goal (deficit for weight loss, surplus for muscle gain), then split into protein, carbs, and fat based on your chosen diet type.
How much protein do I need per day?
General recommendations range from 0.8g per kg of body weight for sedentary adults to 1.6–2.2g per kg for athletes and those building muscle. This calculator adjusts protein based on your goal — higher for muscle gain and body recomposition, moderate for maintenance and weight loss.
What is the difference between BMR and TDEE?
BMR (Basal Metabolic Rate) is the calories your body burns at complete rest. TDEE (Total Daily Energy Expenditure) includes BMR plus all calories burned through daily activities and exercise. You should base your macro targets on TDEE, not BMR.
Which diet type should I choose?
Balanced is best for most people. Choose High Protein if you're building muscle or doing intense training. Low Carb works well for fat loss and blood sugar management. Ketogenic is very low carb for rapid fat loss but is harder to sustain. Low Fat suits endurance athletes and those with heart health concerns.
How accurate is the Mifflin-St Jeor equation?
The Mifflin-St Jeor equation is considered the most accurate BMR formula for most adults, with an accuracy of about ±10%. However, individual factors like muscle mass, genetics, and metabolic conditions can cause variations. Use the results as a starting point and adjust based on your progress.
Should I eat the same macros on rest days?
You can keep macros consistent for simplicity, or slightly reduce carbs on rest days and increase them on training days (carb cycling). Protein and fat intake should generally stay consistent. The total weekly average matters more than daily precision.
How do I track my macronutrient intake?
Use a food tracking app to log meals and scan barcodes. Weigh food with a kitchen scale for accuracy, especially when starting out. Focus on hitting protein targets first, then fill remaining calories with carbs and fats. Most people develop an intuitive sense after a few weeks of tracking.
What is body recomposition?
Body recomposition means simultaneously losing fat and gaining muscle. It works best for beginners, overweight individuals, or those returning to training. It requires a slight calorie deficit (about 5%) with high protein intake (1.6–2.2g/kg) and consistent resistance training.
How often should I recalculate my macros?
Recalculate every 4–6 weeks or whenever your weight changes by more than 2–3 kg, your activity level changes significantly, or you hit a plateau. As you lose weight, your TDEE decreases, so your macro targets need to be adjusted downward to continue progress.