Calculate your Basal Metabolic Rate, daily calorie needs & macronutrient targets
| Activity Level | Multiplier | Description |
|---|---|---|
| Sedentary | 1.2 | Desk job, no exercise |
| Lightly Active | 1.375 | Light exercise 1-3 days/week |
| Moderately Active | 1.55 | Moderate exercise 3-5 days/week |
| Very Active | 1.725 | Hard exercise 6-7 days/week |
| Super Active | 1.9 | Physical job + hard exercise |
Our BMR Calculator estimates the calories your body burns at complete rest using scientifically validated equations. It then calculates your Total Daily Energy Expenditure (TDEE) based on activity level.
Mifflin-St Jeor (1990): Most accurate modern equation. BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age) + 5 (male) or -161 (female).
Harris-Benedict (1919): Older equation that tends to overestimate BMR by 5-10%. Provided for reference.
TDEE (Total Daily Energy Expenditure) = BMR × Activity Multiplier. This is your maintenance calories. To lose weight, eat 300-500 calories below TDEE. To gain muscle, eat 300-500 calories above TDEE.
What is BMR and why does it matter?
BMR (Basal Metabolic Rate) is the minimum calories your body needs to maintain vital functions at rest. It accounts for 60-75% of your daily calorie burn. Knowing your BMR helps you set accurate calorie targets for weight management.
Why is my BMR decreasing as I age?
BMR naturally declines 2-3% per decade after age 20 due to loss of muscle mass (sarcopenia). Strength training can help maintain muscle and keep BMR higher.
How accurate are BMR calculators?
BMR equations estimate within 10% of actual metabolic rate for most people. For precise measurement, DEXA scans or metabolic carts are needed. Use BMR as a starting point and adjust based on real-world results.
Can I increase my BMR?
Yes! Build muscle through resistance training (muscle burns more calories than fat), eat adequate protein, get enough sleep, and stay hydrated. These habits can increase your metabolic rate by 5-15%.
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