Formula to Calculate Basal Metabolic Rate

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Basal Metabolic Rate (BMR) Calculator

Basal Metabolic Rate (BMR) is the number of calories your body needs to perform basic life-sustaining functions at rest. These functions include breathing, circulation, cell production, nutrient processing, and maintaining body temperature. Your BMR accounts for the majority of your daily calorie expenditure.

Several formulas exist to estimate BMR. We will use the widely accepted Mifflin-St Jeor equation, which is considered one of the most accurate. The formula differs slightly for men and women.

Male Female

Understanding Your BMR

The Mifflin-St Jeor Equation is as follows:

  • 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

Your BMR is a crucial part of understanding your total daily energy expenditure. To determine your total calorie needs for the day, you would multiply your BMR by an activity factor that reflects your exercise and daily movement level. This BMR calculator provides the foundational number for those calculations.

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