Calorie Calculator

How to Calculate Your Daily Calorie Needs

Understanding how many calories your body needs each day is fundamental to managing your weight, whether your goal is to lose fat, build muscle, or simply maintain your current physique. This calculator uses the Mifflin-St Jeor equation, which is widely regarded by nutritionists as the most accurate formula for estimating Basal Metabolic Rate (BMR) in healthy individuals.

Your BMR represents the number of calories your body burns at complete rest just to keep vital functions running, including breathing, circulation, cell production, and temperature regulation. The Mifflin-St Jeor formula accounts for your weight, height, age, and gender to produce this baseline number. For men, the equation is 10 times weight in kilograms plus 6.25 times height in centimeters minus 5 times age minus 5. For women, the constant changes to plus 161 instead of minus 5.

Once your BMR is established, it is multiplied by an activity factor to produce your Total Daily Energy Expenditure (TDEE). Activity multipliers range from 1.2 for sedentary lifestyles to 1.9 for very active individuals who exercise intensely every day. Your TDEE represents the total calories you burn in a typical day including all physical activity. To lose weight at a safe and sustainable pace of roughly half a kilogram per week, a deficit of 500 calories below your TDEE is generally recommended. Conversely, adding 500 calories supports gradual weight gain for those looking to build muscle mass. Remember that these are estimates, and individual metabolism can vary. Track your progress and adjust accordingly.