Free BMR Calculator
Calculate your Basal Metabolic Rate (BMR) - the number of calories your body burns at rest. This is the foundation for understanding your daily caloric needs and creating an effective nutrition plan.
Your Basal Metabolic Rate (BMR) is:
0 calories/day
This is the minimum number of calories your body needs to function at rest.
Want to know how to use this number to reach your fitness goals?
What is BMR (Basal Metabolic Rate)?
Your Basal Metabolic Rate (BMR) is the number of calories your body burns at rest to maintain basic physiological functions like breathing, circulation, and cell production. It accounts for 60-75% of your total daily energy expenditure.
How to Use Your BMR for Weight Management
For Weight Loss
Eat 300-500 calories below your BMR + activity level. This creates a sustainable calorie deficit for healthy weight loss.
For Weight Gain
Eat 300-500 calories above your BMR + activity level. This provides the surplus needed for muscle building.
Factors That Affect Your BMR
- Gender: Men typically have higher BMR due to more muscle mass
- Body Composition: Muscle burns more calories than fat at rest
- Genetics: Some people naturally have faster or slower metabolisms
- Hormones: Thyroid function significantly impacts metabolic rate
BMR Myths vs. Facts
❌ Common Myth
"Your metabolism slows down every year after your 20s"
Many people believe their metabolism declines 1-2% per year starting in their 20s, leading to inevitable weight gain.
✅ Scientific Fact
Metabolism remains stable from age 20 to 60
A major 2021 study published in Science analyzed over 6,400 people across 29 countries and found that metabolic rate stays remarkably stable throughout adult life. Read the full study coverage here.
Key findings: Metabolism only begins to decline after age 60, and even then by less than 1% annually. There's no significant difference between men and women after accounting for body size and composition.
What This Means for You
If you're gaining weight in your 30s, 40s, or 50s, it's not because your metabolism is slowing down. The real culprits are likely changes in activity levels, eating habits, sleep patterns, or stress levels. This is actually good news - it means you have more control over your weight than you might think!
Important Note
This calculator provides an estimate. For personalized nutrition guidance tailored to your specific goals, schedule a consultation with our San Diego personal trainers.
Need Help with Your Nutrition Plan?
Knowing your BMR is just the beginning. Our certified personal trainers in San Diego can help you create a comprehensive nutrition and fitness plan that works with your lifestyle and goals.