BMR Calculator
Calculate your Basal Metabolic Rate (BMR) and daily calorie needs based on your activity level.
BMR Calculator
Basal Metabolic Rate
Calorie Targets
About BMR and TDEE
Basal Metabolic Rate (BMR) is the number of calories your body needs to maintain basic physiological functions while at complete rest. This includes breathing, circulation, cell production, and other basic bodily functions.
Total Daily Energy Expenditure (TDEE) is the total number of calories your body burns in a 24-hour period, including your BMR plus the calories burned through activity and digestion of food.
BMR Calculation Formulas
Mifflin-St Jeor Formula (Recommended)
This is the most recent and considered the most accurate formula for calculating BMR:
- For men: BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age in years) + 5
- For women: BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age in years) - 161
Harris-Benedict Formula
This is an older but still widely used formula:
- For men: BMR = 66 + (13.7 × weight in kg) + (5 × height in cm) - (6.8 × age in years)
- For women: BMR = 655 + (9.6 × weight in kg) + (1.8 × height in cm) - (4.7 × age in years)
Katch-McArdle Formula
This formula takes into account lean body mass, which can provide a more accurate estimate for people with lower or higher body fat percentages:
- BMR = 370 + (21.6 × Lean Body Mass in kg)
- Where Lean Body Mass (LBM) = Total Weight in kg × (1 - Body Fat % / 100)
Activity Multipliers
To calculate your TDEE, your BMR is multiplied by an activity factor:
- Sedentary (little or no exercise): BMR × 1.2
- Lightly active (light exercise/sports 1-3 days/week): BMR × 1.375
- Moderately active (moderate exercise/sports 3-5 days/week): BMR × 1.55
- Very active (hard exercise/sports 6-7 days a week): BMR × 1.725
- Extra active (very hard exercise, physical job or training twice a day): BMR × 1.9
Using Your BMR and TDEE
These calculations provide a starting point for understanding your daily calorie needs:
- For weight maintenance: Consume calories equal to your TDEE
- For weight loss: Consume fewer calories than your TDEE (typically 500 calories less per day for 1 pound of weight loss per week)
- For weight gain: Consume more calories than your TDEE (typically 500 calories more per day for 1 pound of weight gain per week)
Limitations
While BMR and TDEE calculations are useful estimates, they do have limitations:
- They don't account for individual variations in metabolism
- They don't consider specific health conditions
- Actual calorie needs may vary based on factors like genetics, hormone levels, and body composition
- Activity levels are subjective and can be difficult to accurately assess
For the most accurate assessment of your calorie needs, consider consulting with a healthcare professional or registered dietitian.