BMR Calculator
Calculate your Basal Metabolic Rate - calories burned at rest
Example: 30-year-old Male
What is BMR?
Basal Metabolic Rate (BMR) is the number of calories your body needs to perform basic life-sustaining functions while at complete rest. This includes breathing, circulating blood, producing cells, and maintaining body temperature.
BMR vs TDEE:
- • BMR: Calories burned at complete rest (sleeping, lying down)
- • TDEE: Total Daily Energy Expenditure including all activity
- • Your TDEE is always higher than your BMR because it includes activity multipliers
Factors Affecting BMR:
- • Age: BMR decreases ~2% per decade after age 20
- • Gender: Men typically have higher BMR due to more muscle mass
- • Body Composition: Muscle burns more calories than fat tissue
- • Genetics: Some people naturally have faster metabolism
- • Hormones: Thyroid function significantly affects BMR
Formulas Used:
Mifflin-St Jeor (Recommended):
Men: (10 × weight in kg) + (6.25 × height in cm) - (5 × age) + 5
Women: (10 × weight in kg) + (6.25 × height in cm) - (5 × age) - 161
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Comparing BMR Formulas
We use two scientifically-validated formulas to calculate your BMR. Here's how they differ:
| Feature | Mifflin-St Jeor | Harris-Benedict |
|---|---|---|
| Year Developed | 1990 | 1918 (revised 1984) |
| Accuracy | ±10% for most people | ±10-15% for most people |
| Best For | Modern populations, recommended by nutrition experts | Historical reference, still widely used |
| Accounts for Muscle Mass | ||
| Recommended by Dietitians | ||
| Used in Medical Settings |
Our Recommendation
We recommend using the Mifflin-St Jeor formula (shown first in your results) as it's more accurate for modern populations and is the formula of choice among registered dietitians and nutritionists.