Macro Nutrient Calculator
Calculate your daily macronutrient needs based on your personal details, activity level, and fitness goals. Get personalized recommendations for calories, protein, carbohydrates, and fats.
How to Use This Calculator
- Enter your personal information including age, gender, weight, and height
- Select your typical activity level from the dropdown menu
- Choose your fitness goal (weight loss, maintenance, or muscle gain)
- Adjust the protein percentage slider based on your dietary preferences
- Click Calculate to see your personalized daily macronutrient recommendations
Formula Used
BMR = 10 × weight(kg) + 6.25 × height(cm) - 5 × age + s
TDEE = BMR × Activity Factor
Calorie Goal = TDEE × Goal Factor
Where:
- BMR = Basal Metabolic Rate (calories burned at rest)
- s = +5 for males, -161 for females
- Activity Factor = 1.2 (sedentary) to 1.9 (very active)
- Goal Factor = 0.85 (weight loss), 1.0 (maintenance), 1.1 (muscle gain)
Example Calculation
Real-World Scenario:
A 30-year-old male, 175cm tall, weighing 75kg, who exercises 3-5 times a week and wants to maintain his weight.
Given:
- Age = 30 years
- Gender = Male
- Weight = 75 kg
- Height = 175 cm
- Activity Level = Moderately active (3-5 days/week)
- Goal = Maintain Weight
Calculation:
BMR = 10 × 75 + 6.25 × 175 - 5 × 30 + 5 = 750 + 1093.75 - 150 + 5 = 1698.75 calories
TDEE = 1698.75 × 1.55 (moderate activity factor) = 2633 calories
Calorie Goal = 2633 × 1.0 (maintenance factor) = 2633 calories
Result: Daily needs: 2633 calories, 165g protein (25%), 330g carbs (50%), 88g fat (25%)
Why This Calculation Matters
Practical Applications
- Optimize athletic performance and recovery
- Support healthy weight management
- Ensure adequate protein for muscle maintenance
- Balance energy levels throughout the day
Key Benefits
- Personalized nutrition based on your body and goals
- Eliminates guesswork in meal planning
- Supports sustainable dietary changes
- Provides foundation for healthy eating habits
Common Mistakes & Tips
Frequently Asked Questions
References & Disclaimer
Nutritional Disclaimer
This macro nutrient calculator provides estimates based on established formulas and should be used as a general guide. Individual nutritional needs may vary based on genetics, medical conditions, medications, and other factors. Consult with a registered dietitian or healthcare provider before making significant changes to your diet, especially if you have underlying health conditions.
References
- A Systematic Review of the Evidence for a Higher Protein Intake for Optimal Body Composition - A review of protein requirements for body composition changes
- International Society of Sports Nutrition Position Stand: Nutrient Timing - Guidelines on nutrient timing for athletes
- Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids - Institute of Medicine guidelines on macronutrient intake
Accuracy Notice
The calculations provided by this calculator are based on the Mifflin-St Jeor equation for basal metabolic rate and standard activity multipliers. While this formula is considered more accurate than older methods like Harris-Benedict, individual metabolic rates can vary by up to 20% from these estimates. Use these calculations as a starting point and adjust based on your actual results and how you feel.
About the Author
Kumaravel Madhavan
Web developer and data researcher creating accurate, easy-to-use calculators across health, finance, education, and construction and more. Works with subject-matter experts to ensure formulas meet trusted standards like WHO, NIH, and ISO.