Calorie Calculator - Daily Calorie Needs & Macro Breakdown
Free online calorie calculator. Calculate your Basal Metabolic Rate (BMR), Total Daily Energy Expenditure (TDEE), and daily caloric needs for weight loss, maintenance, or muscle gain.
Inputs
🔒 Local Processing| Goal Strategy | Daily Target | Weekly Projected Change |
|---|---|---|
| Fast Weight Loss (-1000) | 1,649 kcal | -1.0 kg / week |
| Mild Fat Loss (-500) | 2,149 kcal | -0.5 kg / week |
| Maintenance (TDEE) | 2,649 kcal | 0 kg (Steady weight) |
| Lean Muscle Gain (+300) | 2,949 kcal | +0.3 kg / week |
How to Use This Calculator
- Enter your chronological age, biological sex, current weight, and height.
- Select your average weekly physical activity level from sedentary to very active.
- Review your baseline BMR, maintenance TDEE, and recommended daily calorie targets for weight loss or muscle building.
Formula & Mathematical Method
Uses the scientifically validated Mifflin-St Jeor formula where s = +5 for biological males and s = -161 for biological females. TDEE is computed as BMR × Activity Factor.
BMR = 10×weight(kg) + 6.25×height(cm) - 5×age + sExplanation of Variables
| Symbol | Variable Name | Description & Role in Calculation |
|---|---|---|
| W | Weight (kg) | Current body mass in kilograms. |
| H | Height (cm) | Standing height in centimeters. |
| A | Age (Years) | Chronological age in years. |
| BMR | Basal Metabolic Rate | Resting energy expenditure required for autonomic organ function. |
| TDEE | Total Energy Expenditure | Daily calorie burn including physical work and exercise. |
Worked Calculation Examples
Active Male Fat Loss
Scenario: 28-year-old male, 80kg, 180cm, exercising 4 days/week aiming for mild weight loss.
Sedentary Female Maintenance
Scenario: 30-year-old female, 60kg, 165cm, office job, maintaining weight.
Interpretation of Results
Your daily caloric balance depends on your Basal Metabolic Rate (BMR) and your Total Daily Energy Expenditure (TDEE). Maintaining weight requires consuming calories equal to TDEE; weight loss requires a moderate deficit (typically 300–500 kcal/day), while weight gain requires an intentional surplus.
BMR (Basal Metabolic Rate)
The calories burned by your vital organs (brain, heart, lungs, liver) at complete physical rest over 24 hours.
Key Context: Calorie intake should rarely drop below your BMR without direct medical supervision.
TDEE (Maintenance Calories)
Total calories burned daily accounting for your physical activity, occupational movement, and exercise.
Key Context: Consuming this amount maintains your current body weight under stable activity conditions.
Practical Use Cases
Targeted Weight Loss / Fat Loss Planning
Calculate a safe, sustainable daily caloric target with a moderate deficit for gradual fat loss.
Hypertrophy & Muscle Gain Meal Planning
Estimate the moderate calorie surplus needed to fuel progressive resistance training and muscle protein synthesis.
Limitations & Key Assumptions
- Calculations are based on the Mifflin-St Jeor equation, which estimates resting metabolic rate within ±10% for most healthy adults.
- Individual variation in thyroid hormone function, non-exercise activity thermogenesis (NEAT), and adaptive metabolic downregulation can influence actual caloric expenditure.
- Estimates are provided for nutritional planning purposes only and do not replace personalized guidance from a registered dietitian or physician.