What Is BMR?
Your Basal Metabolic Rate (BMR) is the number of calories your body needs to perform basic life-sustaining functions โ breathing, circulating blood, regulating temperature โ while completely at rest. It typically accounts for 60โ75% of your total daily calorie burn.
Why BMR Matters
BMR is the foundation of any weight management plan. Once you know your BMR, you can calculate your Total Daily Energy Expenditure (TDEE) by applying an activity factor. That number tells you exactly how many calories to eat for weight loss, maintenance, or gain.
The Mifflin-St Jeor Formula
Our calculator uses the Mifflin-St Jeor equation โ the most accurate formula for the general US population:
- Men: (10 ร weight in kg) + (6.25 ร height in cm) โ (5 ร age) + 5
- Women: (10 ร weight in kg) + (6.25 ร height in cm) โ (5 ร age) โ 161
What Affects Your BMR?
- Muscle mass โ more muscle means higher BMR
- Age โ BMR decreases about 2% per decade after 20
- Gender โ men typically have higher BMR than women
- Body size โ larger bodies burn more calories at rest
- Hormones โ thyroid conditions significantly affect BMR