Health
BMR Calculator
Your basal metabolic rate is the energy your body uses just to stay alive — breathing, circulation, cell repair. Enter your stats to calculate BMR with the Mifflin-St Jeor equation.
Quick answer: Your basal metabolic rate is the calories you'd burn at complete rest; the Mifflin-St Jeor equation is the most accurate estimate for most people.
- Sedentary (×1.2)2,085 cal
- Light activity (×1.375)2,389 cal
- Moderate (×1.55)2,693 cal
- Very active (×1.725)2,997 cal
BMR is what your body burns at complete rest, computed with the Mifflin-St Jeor equation. Multiply by an activity factor to estimate your total daily calorie burn (TDEE).
How it works
1. Enter your stats
BMR depends on weight, height, age, and biological sex — all inputs the Mifflin-St Jeor equation uses. Larger and younger bodies generally burn more at rest. Enter accurate measurements for the closest estimate.
2. Apply the Mifflin-St Jeor equation
The calculator uses Mifflin-St Jeor, considered the most accurate BMR formula for the general population. It computes the calories your body needs at complete rest to power vital functions like breathing and circulation. This rest figure excludes any activity.
3. Use BMR as your baseline
Your BMR is the floor of your daily calorie needs — eating below it for long stretches is generally not advised. To find total daily needs, multiply BMR by an activity factor to get TDEE. The calculator gives you the resting number to build from.
Frequently asked questions
What's the difference between BMR and TDEE?
BMR is what you'd burn lying in bed all day. TDEE is BMR plus the calories from daily activity and exercise — always higher than BMR.
Which BMR formula is most accurate?
The Mifflin-St Jeor equation is considered the most accurate for most people and is what this calculator uses.
Why does BMR matter?
It's the foundation for any calorie target. Knowing your BMR helps you set realistic intake goals and understand why crash diets stall metabolism.