BMR Calculator
Mifflin–St Jeor basal metabolic rate.
Enter your values in the interactive calculator to see an instant result. Calculations run in your browser, without an account.
Results are estimates for educational use; confirm important decisions with appropriate experts.
Formula • Worked example • Interpretation
Estimate basal metabolic rate (BMR)
BMR is an estimate of energy used at rest for basic bodily functions. It is not the same as maintenance calories for an active day.
Calculation method
Worked example
For a 30-year-old male who is 70 kg and 175 cm tall, BMR ≈ 1,649 kcal/day.
What your result means
Total daily energy expenditure is often approximated by multiplying BMR by activity level, but real-world needs vary.
Tips for better calculations
Use the Daily Calorie Calculator when you want a maintenance-energy estimate rather than resting needs.
Assumptions and limitations
Population equations have prediction error and may not suit pregnancy, childhood or some medical conditions. Sex-category constants reflect the equation’s original datasets.
SiCalcs tools provide estimates and educational calculations; they do not replace professional financial, medical, tax, or legal advice.