BMR Calculator
Estimate the calories your body burns at rest each day, using the Mifflin-St Jeor equation.
Enter your details below.
How to use
- Enter your weight in kilograms and height in centimetres.
- Enter your age and select Male or Female.
- Read your estimated daily calories at rest.
About this tool
Your Basal Metabolic Rate (BMR) is roughly how many calories your body would burn in a day if you did nothing at all — just breathing, keeping warm, and keeping your organs running. This tool uses the Mifflin-St Jeor formula, which combines weight, height, age, and sex. The result is general information only, not medical advice, and real energy needs vary with muscle mass, hormones, and health conditions.
Frequently asked questions
Is BMR the same as total daily calories?
No — BMR covers rest only. Your total daily burn is higher because it also includes movement, digestion, and exercise.
Why does sex change the result?
The Mifflin-St Jeor equation adds a small constant for men and subtracts one for women, reflecting average differences in body composition.