Calculate your Body Mass Index (BMI) using metric or imperial units. Get instant results and understand your BMI category.
Enter your weight in kilograms
Enter your height in centimeters
Body Mass Index, commonly known as BMI, is a widely used tool to assess whether a person has a healthy body weight for their height. While BMI is not a perfect measure of health, it provides a useful starting point for understanding your weight status and potential health risks. This comprehensive guide will help you understand BMI, how to calculate it, and what your BMI means for your health.
BMI is a measure of body fat based on height and weight that applies to adult men and women. It was developed in the 1830s by Belgian mathematician Adolphe Quetelet and has since become a standard tool used by healthcare professionals worldwide. BMI provides a simple numeric measure of a person's thickness or thinness, allowing health professionals to discuss weight problems more objectively with their patients.
BMI is calculated using a simple formula that takes into account your height and weight. There are two main formulas depending on whether you use metric or imperial units:
BMI = Weight (kg) / [Height (m)]²
For example, if you weigh 70 kg and are 1.75 m tall:
BMI = 70 / (1.75)² = 70 / 3.0625 = 22.86
BMI = [Weight (lbs) / Height (inches)²] × 703
For example, if you weigh 154 lbs and are 69 inches tall:
BMI = (154 / 69²) × 703 = (154 / 4761) × 703 = 22.86
The World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC) have established standard BMI categories:
If your BMI falls in the normal range, you're generally considered to have a healthy weight for your height. However, this doesn't mean you're automatically healthy - other factors like diet, exercise, and body composition also matter.
Being underweight can indicate malnutrition, underlying health conditions, or other issues. If you're underweight, it's important to consult with a healthcare provider to ensure you're getting adequate nutrition and to rule out any medical conditions.
Being overweight increases your risk of various health conditions, including heart disease, type 2 diabetes, and certain cancers. However, being slightly overweight doesn't necessarily mean you're unhealthy, especially if you're physically active.
Obesity is associated with increased risk of serious health conditions, including cardiovascular disease, type 2 diabetes, sleep apnea, and certain types of cancer. If your BMI indicates obesity, it's important to work with healthcare professionals to develop a safe and effective weight management plan.
While BMI is a useful screening tool, it has several limitations:
Research has shown that BMI is correlated with various health outcomes. However, it's important to remember that correlation doesn't always mean causation, and individual health depends on many factors beyond BMI.
Higher BMI values are associated with increased risk of:
Very low BMI values can also pose health risks:
Our BMI calculator makes it easy to determine your BMI using either metric or imperial units. Simply enter your height and weight, and the calculator will instantly provide your BMI along with your weight category. The calculator also provides additional context about what your BMI means for your health.
After calculating your BMI, consider the following steps:
BMI calculations for children and teens are interpreted differently than for adults. Pediatric BMI uses age and sex-specific percentiles rather than fixed categories. Our calculator is designed for adults aged 18 and older.
BMI may be less accurate for elderly individuals due to changes in body composition, height loss, and other age-related factors. Healthcare providers may use different assessment tools for older adults.
For athletes and highly active individuals, BMI may not accurately reflect health status due to higher muscle mass. Body composition measurements like body fat percentage may be more appropriate.
BMI is a useful tool for assessing weight status, but it's just one piece of the health puzzle. While our BMI calculator provides a quick and easy way to determine your BMI, remember that true health involves many factors including diet, exercise, mental health, and genetics. Use BMI as a starting point for understanding your health, but always consult with healthcare professionals for personalized advice and comprehensive health assessments.
BMI (Body Mass Index) is a measure of body fat based on height and weight. It's calculated by dividing weight in kilograms by height in meters squared (kg/m²).
A healthy BMI range is typically between 18.5 and 24.9. Below 18.5 is considered underweight, 25-29.9 is overweight, and 30 or above is considered obese.
BMI is a general indicator but may not be accurate for athletes with high muscle mass, elderly individuals, or children. Consult a healthcare professional for personalized advice.