CalcKitHow to Use the BMR Calculator
Your BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest โ just keeping you alive: breathing, blood circulation, brain activity. For most people it accounts for 60โ70% of all calories burned in a day, which is why it's the foundation of every diet plan.
Enter your age, gender, height, weight and activity level, then press Calculate BMR. This tool uses the Mifflin-St Jeor equation, considered the most accurate formula for the general population. You'll get your BMR plus your TDEE (Total Daily Energy Expenditure) โ BMR multiplied by your activity factor โ which is the number of calories that maintains your current weight.
Once you know your TDEE, weight goals become simple maths: eat about 500 kcal less per day to lose roughly 0.5 kg per week, or 500 more to gain at a similar rate. Your BMR also explains why crash diets backfire โ eating far below BMR for long periods slows your metabolism and burns muscle.
Use your TDEE as the starting point in our Calorie Calculator to set a daily target, and check body fat percentage alongside weight for the full picture.