How many calories should I eat per day?

Daily calorie needs vary based on age, gender, height, weight, and activity level. Our calculator uses the Mifflin-St Jeor equation to calculate your BMR, then multiplies by an activity factor to determine your Total Daily Energy Expenditure (TDEE).

What is BMR and how is it calculated?

BMR (Basal Metabolic Rate) is the number of calories your body needs at rest to maintain basic physiological functions. We use the Mifflin-St Jeor equation: For men: BMR = 10W + 6.25H - 5A + 5. For women: BMR = 10W + 6.25H - 5A - 161.

How accurate are calorie calculator results?

Calorie calculators provide estimates based on population averages. Individual metabolic rates can vary by ±10-15%. Our calculator uses the most accurate formulas available, but results should be used as starting points and adjusted based on real-world results.

How many calories to lose 1 pound per week?

To lose 1 pound per week, you need a calorie deficit of approximately 3,500 calories total, or 500 calories per day. Our calculator automatically calculates safe deficit recommendations for sustainable weight loss.

What's the difference between BMR and TDEE?

BMR is your baseline calorie needs at rest. TDEE (Total Daily Energy Expenditure) includes BMR plus calories burned through daily activities and exercise. TDEE = BMR × Activity Factor (1.2-1.9 depending on activity level).

Calorie Calculator - Daily Calorie Needs & BMR Calculator

Calculate Your Daily Calorie Needs

Discover your BMR, TDEE, and personalized calorie goals using scientifically-proven formulas. Get detailed breakdowns for weight loss, muscle gain, and maintenance with macro recommendations tailored to your fitness objectives.

⚠️ Health & Science Disclaimer

Important: This calculator provides estimates based on established scientific formulas (Mifflin-St Jeor equation, validated activity multipliers). Individual metabolic rates can vary ±10-15% due to genetics, muscle mass, hormones, and medical conditions.

Not Medical Advice: Results are for educational purposes only and should not replace professional medical advice. Consult healthcare providers before starting any diet or exercise program, especially if you have medical conditions or take medications affecting metabolism.

Data Sources: Formulas based on peer-reviewed research from the American Journal of Clinical Nutrition and validated by registered dietitians.

📚 Understanding Your Calorie Needs

Your daily calorie requirements are determined by two main components: your Basal Metabolic Rate (BMR) and your activity level.

Key Concepts:

BMR (Basal Metabolic Rate): Calories needed for basic body functions at rest (60-75% of total needs)
TDEE (Total Daily Energy Expenditure): BMR + calories burned through activity and exercise
Calorie Deficit: Eating below TDEE to lose weight (500 cal deficit = ~1 lb/week loss)
Calorie Surplus: Eating above TDEE to gain weight (250-500 cal surplus for muscle gain)

Scientific Formulas Used:

Mifflin-St Jeor Equation: Most accurate for general population (±10% accuracy)
Harris-Benedict Equation: Traditional formula, slightly less accurate but widely used
Activity Multipliers: Based on metabolic studies of energy expenditure
Macro Ratios: Evidence-based recommendations for optimal body composition

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