BMR Calculator

BMR Calculator

Calculate your Basal Metabolic Rate

About BMR Calculator

Our Basal Metabolic Rate (BMR) calculator helps you determine the number of calories your body needs at rest to maintain basic life functions. This fundamental measurement is essential for weight management, nutrition planning, and understanding your body's energy requirements.

What is BMR?

BMR represents the minimum number of calories your body needs to perform essential functions like breathing, circulation, cell production, nutrient processing, protein synthesis, and ion transport. It accounts for approximately 60-75% of your total daily calorie expenditure.

Available Formulas

Mifflin-St Jeor

Most accurate for most people, accounts for age, gender, weight, and height

Harris-Benedict

Classic formula, slightly less accurate but widely used

Katch-McArdle

Best for those who know their body fat percentage

Cunningham

Ideal for athletes and very active individuals

Factors Affecting BMR

  • Age: BMR decreases with age due to muscle loss
  • Gender: Men typically have higher BMR due to more muscle mass
  • Body Composition: Muscle tissue burns more calories than fat
  • Body Size: Larger bodies require more energy
  • Hormones: Thyroid function significantly impacts BMR
  • Genetics: Some people naturally have faster or slower metabolisms

How to Use

Enter your age, gender, weight, height, and select the formula that best fits your situation. The calculator will compute your BMR and provide TDEE estimates for different activity levels, helping you set appropriate calorie goals.

BMR vs TDEE

BMR: Calories needed at complete rest
TDEE: Total calories including activity (BMR × Activity Multiplier)

Pro Tip

Use the Mifflin-St Jeor formula for the most accurate results. Your BMR is your metabolic baseline - never eat below this number for extended periods as it can slow your metabolism and cause health issues.