BMR Calculatorحاسبة معدل الأيض الأساسي
Find out how many calories your body burns at complete rest.اكتشف عدد السعرات التي يحرقها جسمك في راحة تامة.
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Understanding your Basal Metabolic Rate
فهم معدل الأيض الأساسي
Your Basal Metabolic Rate is the number of calories your body needs just to stay alive: breathing, circulating blood, repairing cells, and keeping your brain running, all while lying still for 24 hours. It typically makes up 60-75% of total daily calorie burn for most people, which is why understanding it matters more than many realize when planning a diet.
This calculator uses the Mifflin-St Jeor equation, published in 1990 and validated repeatedly since as one of the more accurate predictive formulas for the general population, especially compared to the older Harris-Benedict equation from 1919. For men: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5. For women: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161. The five-point gap between the male and female constants reflects average differences in muscle mass and body composition, since muscle tissue burns more calories at rest than fat tissue.
BMR is not the same as the calories you should eat — it's the floor, not the target. Consistently eating below your BMR for extended periods can signal your body to conserve energy, slow metabolism, and break down muscle rather than fat. That's why this page also shows your estimated needs at five different activity levels: multiplying BMR by an activity factor gives your Total Daily Energy Expenditure (TDEE), a far more useful number for everyday planning. Factors like extreme calorie restriction, certain medications, thyroid conditions, and significant muscle loss with age can all lower real-world BMR below what any formula predicts, so treat this as a solid starting estimate rather than a lab-measured value.