BMI Calculator
Calculate your Body Mass Index (BMI) to assess if your weight is healthy relative to your height.
Your BMI:
Please enter your weight and height.
Understanding Your Body Mass Index (BMI)
The Body Mass Index (BMI) is a widely used screening tool that helps to categorize an individual's weight relative to their height. It's a simple, inexpensive, and non-invasive method to estimate body fat and assess potential health risks associated with weight.
How is BMI Calculated?
The standard formula for calculating BMI is:
BMI = weight (kg) / (height (m) * height (m))
For example, if you weigh 70 kilograms and are 1.75 meters (175 cm) tall, your BMI would be calculated as:
BMI = 70 / (1.75 * 1.75) = 70 / 3.0625 ≈ 22.86
BMI Categories
The World Health Organization (WHO) defines BMI categories for adults as follows:
- Underweight: Less than 18.5
- Normal weight: 18.5 – 24.9
- Overweight: 25 – 29.9
- Obesity: 30 or greater
These categories provide a general guide to help identify potential weight-related health issues. However, it's important to remember that BMI is a screening tool and not a diagnostic one.
Limitations of BMI
While useful, BMI has limitations:
- Muscle Mass: Athletes or individuals with high muscle mass may have a high BMI without having excess body fat, as muscle weighs more than fat.
- Age and Sex: BMI doesn't account for changes in body composition that occur with age or differences between sexes.
- Body Composition: It doesn't distinguish between fat mass and lean mass, nor does it indicate fat distribution (e.g., abdominal fat, which is a higher health risk).
- Ethnicity: Different ethnic groups may have different health risks at the same BMI.
What Your BMI Means for Your Health
A BMI outside the "normal weight" range can be associated with increased health risks:
- Underweight: May indicate malnutrition, osteoporosis, or a weakened immune system.
- Overweight/Obesity: Can increase the risk of heart disease, type 2 diabetes, high blood pressure, certain cancers, and sleep apnea.
It's crucial to consider BMI alongside other factors like waist circumference, diet, physical activity levels, family history, and overall health status. Always consult a healthcare professional for a comprehensive assessment of your health and weight management plan.
Examples:
- Example 1 (Normal Weight): A person weighing 70 kg with a height of 175 cm has a BMI of approximately 22.86, which falls into the normal weight category.
- Example 2 (Overweight): A person weighing 85 kg with a height of 170 cm has a BMI of approximately 29.41, indicating they are overweight.
- Example 3 (Obese): A person weighing 95 kg with a height of 165 cm has a BMI of approximately 34.93, which is classified as obese.