BMR Calculator | Calculate Your Basal Metabolic Rate

Calculate your Basal Metabolic Rate (BMR) with our calculator. It estimates your resting calorie needs for weight loss, maintenance, or gain. Enter your age, gender, height, and weight for personalized results.


Enter Your Details
Personal Information
Valid range: 15-80 years
Body Measurements
feet
inches
centimeters
pounds
kilograms
Select Formula
Your Results
Your Basal Metabolic Rate (BMR):
0
Activity Level Calories
Sedentary (little or no exercise)
0
Light Exercise (1-3 times/week)
0
Moderate Exercise (4-5 times/week)
0
Daily Exercise/Active
0
Very Active (intense exercise 6-7x/week)
0
Extra Active (very intense daily exercise/physical job)
0
Activity Level Details
  • Exercise: 15-30 minutes of elevated heart rate activity
  • Intense exercise: 45-120 minutes of elevated heart rate activity
  • Very intense exercise: 2+ hours of elevated heart rate activity
BMR Calculation Formulas
Calculation Formulas:

Mifflin-St Jeor:

Men: BMR = 10W + 6.25H - 5A + 5
Women: BMR = 10W + 6.25H - 5A - 161

Harris-Benedict:

Men: BMR = 13.397W + 4.799H - 5.677A + 88.362
Women: BMR = 9.247W + 3.098H - 4.330A + 447.593

Katch-McArdle:

BMR = 370 + 21.6(1 - F)W

Where:

  • W = weight in kg
  • H = height in cm
  • A = age
  • F = body fat in decimal form
Energy Distribution:
70%
20%
10%
~70% of daily energy is used for basic functions (BMR)
~20% is used for physical activity
~10% is used for food digestion (thermogenesis)
Factors Affecting BMR
Muscle Mass

Having more muscle mass increases your BMR significantly as muscle tissue requires more energy to maintain than fat tissue. Weight training can help increase muscle mass and boost BMR.

Age

BMR typically decreases with age due to reduced muscle mass and slower metabolic processes. The decrease is approximately 1-2% per decade after age 20.

Gender

Men generally have higher BMRs than women due to greater muscle mass, organ size, and hormonal differences that affect body composition.

Body Temperature

Every increase of 0.5°C in core body temperature increases BMR by about 7%. This is why fever or exposure to extreme temperatures can affect your metabolic rate.

Hormonal Factors

Thyroid hormones, growth hormone, and stress hormones all influence BMR. Conditions affecting these hormones can significantly impact metabolic rate.

Diet and Nutrition

Regular eating patterns maintain BMR, while severe calorie restriction can lower it. Certain foods and supplements may temporarily boost metabolic rate.

Sleep and Recovery

Poor sleep quality or insufficient sleep can lower BMR by affecting hormone production and regulation. Aim for 7-9 hours of quality sleep.

Health Status

Various medical conditions and medications can affect BMR. Chronic diseases, infections, and healing processes often increase metabolic rate.

Genetics

Genetic factors can influence your base metabolic rate by affecting muscle mass potential, hormone levels, and how efficiently your body uses energy.

Medical Disclaimer

This calculator provides estimates only. Consult a healthcare provider before making any dietary or exercise changes.