Want to check your BMR (Basal Metabolic Rate)? Here’s a simple online “BMR calculator” that helps you find out your BMR just by entering your Gender, height, and weight.
BMR Calculator: Basal Metabolic Rate Calculation
What is BMR?
BMR stands for Basal Metabolic Rate. It’s the number of calories your body needs to perform basic life-sustaining functions such as breathing, circulation, and cell production while at rest.
In simple terms, BMR is the amount of energy your body requires to keep you alive and functioning when you’re not doing any physical activities. It doesn’t account for the calories burned through daily activities or exercise; it’s purely the energy required for your body’s essential functions.
Why Should We Calculate BMR?
Knowing your BMR is crucial for several reasons:
- Weight Management: Understanding your BMR helps you to determine how many calories you need to maintain, lose, or gain weight. By knowing your BMR, you can create a more accurate diet plan. If you consume fewer calories than your BMR, you will lose weight, and if you consume more, you will gain weight.
- Health Insights: Your BMR gives you insights into your metabolism and overall health. A higher BMR can mean that your body burns more calories at rest, which is often a sign of a healthy metabolism. Conversely, a lower BMR can indicate a slower metabolism.
- Personalized Diet Plans: With BMR, you can tailor your diet to meet your specific energy needs, ensuring you get the right amount of nutrients without overeating or undereating. For athletes and fitness enthusiasts, knowing their BMR helps in planning their diet to enhance performance and recovery.
How to Calculate BMR?
There are several formulas to calculate BMR, each considering different factors like age, sex, weight, and body composition. Here are three popular methods:
Mifflin-St Jeor Formula
Developed in the 1990s, the Mifflin-St Jeor formula is considered more accurate than some older methods. He gives two different formulas for males and females.
For Men:
BMR = (10 x weight in kg) + (6.25 x height in cm) − (5 x age in years) + 5
For Women:
BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age in years)−161
Example:
A 30-year-old woman weighing 70 kg and 165 cm tall:
BMR = (10×70) + (6.25×165) − (5×30) − 161
BMR = 700 + 1031.25 − 150 − 161
BMR = 1420.25 calories/day
Revised Harris-Benedict Formula
The Harris-Benedict equation was one of the first formulas used to calculate BMR, developed in the early 20th century. It was revised in 1984 to improve accuracy.
For Men:
BMR = 88.362 + (13.397 × weight in kg) + (4.799 × height in cm) − (5.677 × age in years)
For Women:
BMR = 447.593 + (9.247 × weight in kg) + (3.098 × height in cm)−(4.330 × age in years)
Example:
A 30-year-old man weighing 85 kg and 180 cm tall:
BMR = 88.362 + (13.397 × 85) + (4.799 × 180) − (5.677 × 30)
BMR = 88.362 + 1138.745 + 863.82 − 170.31
BMR = 88.362 + 1138.745 + 863.82 − 170.31
BMR = 1920.617 calories/day
Katch-McArdle Formula
This formula is particularly useful for athletes and individuals with a higher muscle mass, as it considers lean body mass.
Formula:
BMR = 370 + (21.6 × lean body mass in kg)
To find lean body mass:
Lean Body Mass = Weight in kg × (1 − Body Fat Percentage)
Example:
A person weighing 75 kg with 20% body fat:
Lean Body Mass = 75 × (1 − 0.20)
Lean Body Mass = 75 × 0.80
Lean Body Mass = 60 kg
BMR = 370 + (21.6 × 60)
BMR = 370+1296
BMR = 1666 calories/day
How to Use Your BMR
Once you have calculated your BMR, you can use this number to better manage your diet and exercise routines. Here are some tips on how to use your BMR effectively:
1. Calculate Total Daily Energy Expenditure (TDEE): Your BMR represents the calories you need at rest. To find out how many calories you need per day considering your activity level, multiply your BMR by an activity factor:
- Sedentary (little or no exercise): BMR x 1.2
- Lightly active (light exercise/sports 1-3 days/week): BMR x 1.375
- Moderately active (moderate exercise/sports 3-5 days/week): BMR x 1.55
- Very active (hard exercise/sports 6-7 days a week): BMR x 1.725
- Super active (very hard exercise/physical job): BMR x 1.9
Pro tip: We have a time-saving solution for you. You don’t need to calculate your TDEE manually. Instead, you can use our free tdee calculator which will save you time and effort.
2. Adjust Caloric Intake for Goals: Depending on your goals, adjust your caloric intake accordingly:
- Weight Loss: Create a calorie deficit by consuming fewer calories than your TDEE.
- Weight Gain: Consume more calories than your TDEE.
- Weight Maintenance: Keep your caloric intake around your TDEE.
3. Monitor and Adjust: Regularly monitor your weight and adjust your caloric intake and activity levels as needed. Remember, these formulas provide estimates, and individual variations can occur.
How to Calculate BMR Using Our Website
Our website offers a convenient and easy-to-use BMR calculator that has three popular formulas: Mifflin-St Jeor, Revised Harris-Benedict, and Katch-McArdle. Here’s a step-by-step guide on how to use our BMR calculator to find your Basal Metabolic Rate.
Step 1: Visit the BMR Calculator Page
Navigate to the BMR calculator page on our website. You’ll find a form where you can enter your details.
Step 2: Enter Your Personal Information
Fill in the required fields with your personal information:
- Age: Enter your age in years.
- Gender: Select your gender (male or female).
- Weight: Enter your weight in kilograms (kg) or pounds (lbs).
- Height: Enter your height in feet (ft), centimeters (cm) or inches (in).
- Body Fat Percentage (Optional): If you know your body fat percentage. This is particularly useful for the Katch-McArdle formula only.
Step 3: Choose the Formula (Optional)
Our calculator allows you to choose between the three formulas. Select one based on your preference by clicking on “show advance setting”.
- Mifflin-St Jeor
- Revised Harris-Benedict
- Katch-McArdle
This is an optional task If you don’t select any formula then by default, the calculator will use the formula by Mifflin-St Jeor which is more accurate.
Step 4: Calculate Your BMR
After entering all the necessary information, click the “Calculate” button. The calculator will instantly provide you with your BMR based on the selected formula.
Step 5: Review Your Results
The result will display your BMR in calories per day. This is the number of calories your body needs to maintain basic physiological functions while at rest.
Conclusion
Understanding your BMR is an important step towards achieving your health and fitness goals. By knowing how many calories your body needs at rest, you can make the right decisions about your diet and activity levels.
Use the formulas above to calculate your BMR manually or instead of doing time-consuming mathematical tasks, you can use our free BMR calculator tool which is at the top of this page, and start your journey towards a healthier lifestyle today!
Knowing your BMR gives you a solid foundation, whether you want to lose weight, gain muscle, or maintain your current body state.