About the BMR Calculator
A BMR calculator estimates your Basal Metabolic Rate: the energy your body uses at complete rest to keep you alive (breathing, circulation, cell function). It is the baseline before any activity. This tool shows BMR from both the modern Mifflin-St Jeor equation and the classic Harris-Benedict equation.
How BMR Calculator works
Mifflin-St Jeor: BMR = 10×kg + 6.25×cm − 5×age + s (s = +5 men, −161 women).
Harris-Benedict (revised): men = 88.362 + 13.397×kg + 4.799×cm − 5.677×age; women = 447.593 + 9.247×kg + 3.098×cm − 4.330×age.
Example: 30-year-old man, 175 cm, 70 kg → Mifflin BMR ≈ 1,649 kcal/day.
Common uses
- Find your resting calorie burn (BMR)
- Use as the base for daily calorie needs (TDEE)
- Compare Mifflin-St Jeor and Harris-Benedict results
- Plan calorie targets for weight goals
Frequently asked questions
What is BMR?
Basal Metabolic Rate — the calories your body burns at rest to maintain basic functions. It is usually 60–70% of your total daily burn.
Which formula is best?
Mifflin-St Jeor is considered the most accurate for most people; Harris-Benedict is the older standard.
How do I get daily calories from BMR?
Multiply BMR by an activity factor (1.2–1.9). The Calorie Calculator does this for you.