Your Measurements
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What is BMR?
Basal Metabolic Rate is the number of calories your body needs to maintain basic physiological functions while completely at rest.
60-75% of Daily Calories
Your BMR accounts for the majority of your daily calorie burn -- breathing, circulation, cell production, and temperature regulation all happen without you lifting a finger.
The Foundation for TDEE
Multiply your BMR by an activity factor to get your Total Daily Energy Expenditure (TDEE) -- the actual number of calories you burn each day.
Changes With Age
BMR naturally decreases as you age, losing roughly 1-2% per decade after 20. Regular strength training helps preserve metabolic rate by maintaining muscle mass.
Mifflin-St Jeor Equation (Most Accurate)
How to Use Your BMR
- Multiply BMR by your activity factor to estimate TDEE
- Eat below TDEE to lose weight; above TDEE to gain weight
- BMR decreases with age -- recalculate at least annually
- Never eat below your BMR for extended periods -- this can slow metabolism
Related Calculators
Your BMR is just the beginning. Use these tools to build a complete nutrition picture.
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