Calorie Calculator
Free calorie calculator: estimate your BMR with the Mifflin-St Jeor equation and find your total daily calorie needs based on your activity level.
About this tool
Your body burns a certain number of calories every day just keeping you alive - breathing, thinking, keeping warm - plus whatever your activity adds on top. Eat more than that and you gain weight; eat less and you lose it.
This calorie calculator estimates your Basal Metabolic Rate (BMR) with the Mifflin-St Jeor equation, then multiplies by your activity level to give your total daily calorie needs.
How to use
Enter your age, select your gender, and type your height in centimeters and weight in kilograms. Then choose the activity level that best matches your week, from sedentary to very active.
Press Calculate Calories to see your BMR - what you burn at rest - and your total daily needs. To lose about half a kilo per week, most people aim for roughly 500 calories below this number.
The math behind it
The Mifflin-St Jeor equation: for men, BMR = 10 x weight(kg) + 6.25 x height(cm) - 5 x age + 5; for women, the same but minus 161 instead of plus 5.
Daily needs = BMR x activity factor (1.2 sedentary up to 1.9 very active). It is an estimate - individual metabolism varies by about 10%.