Calorie Calculator: Complete Guide to BMR & TDEE

Calories are the foundation of weight management, fitness, and health. Whether you want to lose fat, build muscle, or maintain your weight, understanding your daily calorie needs is the single most important step to success. Our Calorie Calculator uses the scientifically validated Mifflin-St Jeor formula to calculate your BMR and TDEE with exceptional accuracy.

This tool is trusted by personal trainers, nutritionists, and fitness enthusiasts worldwide to create realistic, sustainable, and effective nutrition plans.

What Is BMR?

Basal Metabolic Rate (BMR) is the number of calories your body burns at rest to keep vital functions working, including breathing, cell production, nutrient processing, and organ function. BMR represents about 60–75% of your total daily calories burned.

What Is TDEE?

Total Daily Energy Expenditure (TDEE) is your BMR multiplied by your activity level. It represents the total calories you burn in an average day. TDEE is the most important number for weight management.

How It Works

• Maintenance: Eat = TDEE → weight stays the same
• Fat Loss: Eat < TDEE → body uses stored fat
• Muscle Gain: Eat > TDEE → body builds muscle

Activity Levels Explained

• Sedentary: Little to no exercise, desk job
• Light Activity: 1–3 days/week light exercise
• Moderate Activity: 3–5 days/week moderate exercise
• Active: 6–7 days/week hard exercise
• Very Active: Physical labor + daily training

Calorie Goals Explained

• Maintain: TDEE → no gain, no loss
• Mild Weight Loss: TDEE − 300 → safe, sustainable
• Fast Weight Loss: TDEE − 500 → 0.5kg per week
• Muscle Gain: TDEE + 200–300 → clean bulking

Why 3500 Calories = 0.5kg Fat

One kilogram of body fat equals approximately 7700 calories. This means a daily deficit of 500 calories leads to about 0.5kg of fat loss per week — the gold standard for healthy, sustainable weight loss.

Who Should Use This Calculator?

• People who want to lose weight safely
• Fitness enthusiasts building muscle
• Anyone maintaining a healthy lifestyle
• Athletes optimizing performance
• Nutritionists and personal trainers

How to Use This Calculator

1. Enter your age, gender, weight, and height
2. Select your activity level
3. Choose your goal (maintain, lose, gain)
4. Get your personalized calorie plan
5. Enter target weight to see your timeline
6. Follow your calorie plan for consistent results

Scientific Formula Used

Male BMR: 88.362 + (13.397 × weight) + (4.799 × height) − (5.677 × age)

Female BMR: 447.593 + (9.247 × weight) + (3.098 × height) − (4.330 × age)

TDEE = BMR × Activity Multiplier

Important Tips

• Recalculate every 4–6 weeks as weight changes
• Prioritize protein for muscle retention
• Stay hydrated and sleep 7–9 hours
• Use weight training to preserve muscle
• Be consistent — results take time

Final Notes

This calculator provides an estimate based on scientific formulas. Individual results may vary due to genetics, hormones, stress, and lifestyle. Use this tool as a powerful starting point for your health journey.

Calorie management is not about restriction — it’s about intelligence. With the right numbers, you can transform your body safely, permanently, and confidently.