Use this free online BMR calculator to estimate your Basal Metabolic Rate and Total Daily Energy Expenditure (TDEE) using the Mifflin-St Jeor equation. Enter your gender, weight, height, age, and activity level to find out how many calories your body needs each day. This tool is for general informational purposes only and is not a substitute for professional medical or nutritional advice.
How to Use the BMR Calculator
Select your Gender from the dropdown.
Enter your Weight (kg) and Height (cm).
Enter your Age (years).
Choose your Activity Level that best matches your weekly exercise routine.
Click "Calculate BMR & TDEE" to see your BMR and daily calorie needs.
Frequently Asked Questions
This calculator uses the Mifflin-St Jeor equation: 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.
BMR is the number of calories your body burns at complete rest just to maintain basic functions. TDEE (Total Daily Energy Expenditure) multiplies BMR by an activity factor to estimate how many calories you burn in a full day, including exercise and daily movement.
Each activity level applies a different multiplier to your BMR, ranging from 1.2 for a sedentary lifestyle up to 1.9 for very intense daily exercise, so choosing the option closest to your real routine gives a more accurate TDEE.
If weight, height, or age is missing, zero, or negative, the calculator shows an "Invalid input!" message and does not calculate a BMR or TDEE value. Remember this tool offers general estimates only and isn't a substitute for professional medical advice.