BMR Calculator

Understanding Basal Metabolic Rate (BMR)

Basal Metabolic Rate (BMR) is the number of calories your body needs to maintain basic physiological functions at rest, such as breathing, circulation, and cell production. It represents the minimum energy required to keep your body functioning while you're not doing any physical activities.

Details

BMR varies from person to person based on factors like age, gender, weight, height, and body composition. Calculating your BMR can help you understand how many calories your body needs to perform essential functions, which is useful for planning diet and exercise routines.

The most commonly used formulas to estimate BMR are the Harris-Benedict Equation and the Mifflin-St Jeor Equation. These equations use your personal data to calculate your BMR.

Harris-Benedict Equation

• For Men:

  BMR = 88.36 + (13.4 × weight in kg) + (4.8 × height in cm) – (5.7 × age in years)

• For Women:

  BMR = 447.6 + (9.2 × weight in kg) + (3.1 × height in cm) – (4.3 × age in years)

Mifflin-St Jeor Equation

• For Men:

  BMR = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) + 5

• For Women:

  BMR = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) – 161

Examples

Example 1: Calculating BMR for a Woman

Person A:

• Gender: Female
• Age: 30 years
• Weight: 65 kg
• Height: 170 cm

Using the Mifflin-St Jeor Equation:

BMR = (10 × 65) + (6.25 × 170) – (5 × 30) – 161
BMR = 650 + 1062.5 – 150 – 161
BMR = 1401.5 kcal/day

Result: Person A's BMR is approximately 1,402 calories per day.

Example 2: Calculating BMR for a Man

Person B:

• Gender: Male
• Age: 40 years
• Weight: 80 kg
• Height: 180 cm

Using the Mifflin-St Jeor Equation:

BMR = (10 × 80) + (6.25 × 180) – (5 × 40) + 5
BMR = 800 + 1125 – 200 + 5
BMR = 1730 kcal/day

Result: Person B's BMR is approximately 1,730 calories per day.

Other Helpful Info

• Total Daily Energy Expenditure (TDEE):

  Your BMR accounts for the calories needed at rest. To maintain your current weight, you need to consider your Total Daily Energy Expenditure, which includes physical activities.

  TDEE = BMR × Activity Level Multiplier

  • Sedentary (little or no exercise): TDEE = BMR × 1.2
  • Lightly active (light exercise/sports 1-3 days/week): TDEE = BMR × 1.375
  • Moderately active (moderate exercise/sports 3-5 days/week): TDEE = BMR × 1.55
  • Very active (hard exercise/sports 6-7 days a week): TDEE = BMR × 1.725
  • Extra active (very hard exercise/sports & physical job): TDEE = BMR × 1.9
• Weight Management:
  • To lose weight: Consume fewer calories than your TDEE.
  • To gain weight: Consume more calories than your TDEE.
  • To maintain weight: Consume calories equal to your TDEE.
• Factors Affecting BMR:
  • Muscle Mass: More muscle increases BMR.
  • Age: BMR decreases with age due to loss of muscle mass.
  • Genetics: Genetic factors can influence metabolism.
  • Hormonal Factors: Thyroid hormones significantly affect BMR.
• Importance of BMR:

  Knowing your BMR helps in planning diets and understanding your body's energy needs. It aids in setting realistic goals for weight loss, gain, or maintenance.

• Consult Professionals:

  For personalized advice, consider consulting a nutritionist or healthcare provider, especially before making significant changes to your diet or exercise routine.

Use our BMR Calculator to estimate your Basal Metabolic Rate and gain insights into your body's daily caloric needs. This information can be a valuable starting point for developing a nutrition and fitness plan tailored to your goals.