BMR Calculator
Calculate your Basal Metabolic Rate and understand your body’s energy needs
Your BMR Results
Basal Metabolic Rate (BMR)
Daily Calorie Needs
Weekly Maintenance
Activity Level Multipliers
What is BMR?
BMR (Basal Metabolic Rate) is the number of calories your body needs to perform basic life-sustaining functions at complete rest. These functions include breathing, circulation, cell production, nutrient processing, and maintaining body temperature.
Your BMR accounts for approximately 60-75% of your total daily energy expenditure (TDEE), making it the largest component of your calorie needs. Understanding your BMR is essential for effective weight management, as it represents the minimum number of calories your body requires to function properly.
Why Knowing Your BMR Matters
Weight Management
Knowing your BMR helps you create effective diet plans for weight loss or gain
Metabolic Health
Understanding your metabolism helps identify potential health issues
Nutrition Planning
Create personalized nutrition plans based on your specific metabolic needs
Progress Tracking
Monitor changes in your metabolism as you lose weight or build muscle
Factors That Affect Your BMR
Several factors influence your Basal Metabolic Rate:
- Gender: Men typically have higher BMRs than women due to greater muscle mass
- Age: BMR decreases with age as muscle mass declines
- Weight: Heavier people have higher BMRs
- Height: Taller people have higher BMRs due to greater surface area
- Genetics: Some people naturally have faster or slower metabolisms
- Body Composition: Muscle tissue burns more calories at rest than fat tissue
How to Use Our BMR Calculator
Enter Your Details
Input your age, gender, weight, and height using either metric or imperial units
Select Formula
Choose between different BMR calculation formulas (Mifflin-St Jeor is recommended)
Calculate
Click calculate to see your BMR and daily calorie needs
Apply Activity Multipliers
Use the activity multipliers to estimate your total daily calorie needs based on your exercise level
BMR Calculation Formulas
Our calculator uses three different formulas to estimate your BMR:
Mifflin-St Jeor Equation (Most Accurate)
Developed in 1990, this is considered the most accurate formula for estimating BMR in healthy individuals:
- For men: BMR = 10 × weight(kg) + 6.25 × height(cm) – 5 × age(y) + 5
- For women: BMR = 10 × weight(kg) + 6.25 × height(cm) – 5 × age(y) – 161
Original Harris-Benedict Equation
Developed in 1919, this was the standard for many years but tends to overestimate BMR:
- For men: BMR = 66.5 + (13.75 × weight(kg)) + (5.003 × height(cm)) – (6.755 × age(y))
- For women: BMR = 655.1 + (9.563 × weight(kg)) + (1.850 × height(cm)) – (4.676 × age(y))
Revised Harris-Benedict Equation
Updated in 1984 to improve accuracy:
- For men: BMR = 88.362 + (13.397 × weight(kg)) + (4.799 × height(cm)) – (5.677 × age(y))
- For women: BMR = 447.593 + (9.247 × weight(kg)) + (3.098 × height(cm)) – (4.330 × age(y))
Frequently Asked Questions
Our calculator uses scientifically validated formulas to estimate your BMR. The Mifflin-St Jeor equation is considered the most accurate for most people. However, individual variations can occur due to genetics, body composition, and other factors. Use the results as a starting point and adjust based on your actual progress.
Your BMR represents the minimum number of calories your body needs to function at rest. To lose weight, you need to create a calorie deficit by consuming fewer calories than your total daily energy expenditure (which includes your BMR plus activity calories). To gain weight, you need a calorie surplus. Understanding your BMR helps you set appropriate calorie targets for your goals.
You can increase your BMR by building muscle through strength training, as muscle tissue burns more calories at rest than fat tissue. Other strategies include eating enough protein, staying hydrated, getting quality sleep, and incorporating high-intensity interval training (HIIT) into your exercise routine.
You should recalculate your BMR whenever your weight changes significantly (5+ kg), or every 2-3 months. As you lose weight, your BMR decreases, so you may need to adjust your calorie intake accordingly to continue making progress toward your goals.
BMR (Basal Metabolic Rate) and RMR (Resting Metabolic Rate) are often used interchangeably, but there’s a slight difference. BMR is measured under very restrictive conditions (complete rest, fasting, and in a controlled environment), while RMR is measured under less strict conditions. For practical purposes, the difference is minimal, and both represent the calories your body burns at rest.