
BMR Calculator
BMR Calculator
Calculate Your Basal Metabolic Rate Accurately
Understanding your body’s calorie needs is the foundation of sustainable weight management and metabolic health.
Calculate Your BMR
Your Basal Metabolic Rate (BMR)
calories per day at complete rest
Weight Maintenance
calories/day
Weight Loss
calories/day
Weight Gain
calories/day
What Is BMR (Basal Metabolic Rate)?
Basal Metabolic Rate (BMR) is the number of calories your body requires to perform essential life-sustaining functions while at complete rest, including:
- Breathing – Oxygen intake and carbon dioxide expulsion
- Blood circulation – Maintaining blood flow throughout the body
- Brain and nerve function – Neural activity and cognitive processes
- Cell repair and regeneration – Tissue maintenance and healing
- Maintaining body temperature – Thermal regulation
- Organ function – Heart, liver, kidney, and other organ operations
In simple terms, BMR represents the minimum calories your body needs to survive without any physical activity. It accounts for 60-70% of your total daily calorie expenditure.
Why BMR Is Important for Weight Management
Your BMR accounts for 60–70% of your total daily calorie expenditure. Ignoring it often leads to:
- Ineffective dieting – Setting unrealistic calorie goals
- Metabolic slowdown – Body adapts to conserve energy
- Muscle loss – Body breaks down muscle for energy
- Weight regain – Yo-yo dieting effects
- Nutrient deficiencies – Inadequate energy for bodily functions
By calculating your BMR, you can:
- Avoid extreme calorie restriction – Prevent metabolic damage
- Set realistic weight-loss targets – Sustainable 0.5-1kg per week
- Maintain muscle mass – Preserve lean tissue during weight loss
- Improve long-term metabolic health – Support overall wellbeing
- Optimize athletic performance – Fuel training and recovery
How This BMR Calculator Works
This calculator uses the Mifflin-St Jeor Equation, which is widely regarded as the most accurate BMR formula for healthy adults. This formula is supported by clinical research and is preferred by nutritionists and dietitians worldwide.
BMR Formula Used
For Men:
BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age (years) + 5
For Women:
BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age (years) − 161
Example: 30-year-old male, 70kg, 175cm
BMR = (10 × 70) + (6.25 × 175) − (5 × 30) + 5 = 700 + 1093.75 − 150 + 5 = 1,648.75 calories/day
What Is TDEE and Daily Calorie Needs?
Your Total Daily Energy Expenditure (TDEE) is calculated by multiplying your BMR by an activity factor, reflecting how active you are. Your TDEE represents the calories required to maintain your current weight.
| Activity Level | Multiplier | Description |
|---|---|---|
| Sedentary | 1.2 | Little or no exercise, desk job |
| Lightly Active | 1.375 | Light exercise 1-3 days/week |
| Moderately Active | 1.55 | Moderate exercise 3-5 days/week |
| Very Active | 1.725 | Hard exercise 6-7 days/week |
| Extra Active | 1.9 | Physical job or intense daily training |
Using BMR for Weight Management
For Weight Loss:
- Reduce 500 calories per day from your TDEE
- Leads to ~0.5 kg (1 lb) fat loss per week
- Safer and more sustainable than crash dieting
- Preserves muscle mass when combined with protein and strength training
For Weight Gain:
- Add 500 calories per day to your TDEE
- Supports muscle growth when combined with strength training
- Ensures adequate energy for recovery and performance
- Promotes healthy weight gain (primarily muscle)
Accuracy and Limitations
While this BMR calculator is scientifically reliable, it provides estimates, not medical diagnoses. Results may vary due to hormonal conditions, muscle mass differences, genetics, or medical conditions. For personalized nutrition planning, consult a qualified healthcare or nutrition professional.
Our BMR Calculator is designed to help you make smart, evidence-based decisions about your health and nutrition. Combine accurate calorie data with balanced meals, proper sleep, and regular activity for best results.
Frequently Asked Questions
Is this calculator suitable for women?
Yes. It uses a gender-specific formula for accurate results. Women typically have lower BMR than men of the same age, weight, and height due to differences in body composition and hormones.
How often should I recalculate my BMR?
Recalculate whenever your weight changes by 5+ kg, your age changes, or your activity level significantly changes. For weight loss programs, recalculate every 4-6 weeks to ensure your calorie targets remain accurate.
Can muscle mass affect BMR?
Yes. Muscle tissue is metabolically active and burns more calories at rest than fat tissue. Research shows that increasing muscle mass can significantly boost your basal metabolic rate compared to individuals with higher body fat percentages.
Who should use a BMR calculator?
This tool is ideal for people planning weight loss, athletes adjusting calorie intake, and those interested in metabolic health. It provides the baseline energy requirements needed to support vital organ functions.