BMR Calculator
Estimate your basal metabolic rate, the number of calories your body would burn in a day at complete rest just to keep essential functions running like breathing, circulation and cell repair. Enter your age, sex, height and weight, and the calculator uses the Mifflin-St Jeor equation, widely regarded as one of the most accurate predictive formulas for everyday use. Your BMR is the foundation for any calorie plan: your total daily needs are your BMR scaled up by how active you are. Knowing this baseline helps you understand why very low-calorie diets can be counterproductive. This is an estimate for general guidance, not a substitute for professional advice, and everything is computed locally in your browser.
How to use BMR Calculator
- Enter your age and sex.
- Enter your height and weight.
- Read your basal metabolic rate in calories per day.
Frequently asked questions
What equation does this BMR calculator use?
It uses the Mifflin-St Jeor equation, which is widely regarded as one of the most accurate for estimating basal metabolic rate.
What does BMR actually measure?
BMR is the calories your body burns at complete rest just to keep basic functions running, before any activity is added.
Why does BMR differ by sex?
The Mifflin-St Jeor formula adds a constant for men and subtracts one for women, reflecting average differences in lean body mass.
What is BMR Calculator?
Estimate your basal metabolic rate, the number of calories your body would burn in a day at complete rest just to keep essential functions running like breathing, circulation and cell repair. Enter your age, sex, height and weight, and the calculator uses the Mifflin-St Jeor equation, widely regarded as one of the most accurate predictive formulas for everyday use.
Is BMR Calculator free to use?
Yes. BMR Calculator is completely free, with no sign-up and no usage limits.
Does BMR Calculator work in a web browser?
Yes. BMR Calculator runs in any modern web browser. There is nothing to download or install.
Is my data private with BMR Calculator?
Yes. BMR Calculator runs entirely on your device in your browser, so nothing you enter is uploaded to a server.
Badge
Link this tool from a README, doc or site. The badge links back to this page.
[](https://yourhack.ai/bmr-calculator)