Health & Fitness
BMI Calculator
Calculate your Body Mass Index (BMI) to assess if you're at a healthy weight for your height.
Enter your height and weight to see your BMI results
Related to BMI Calculator
The Body Mass Index (BMI) calculator uses a mathematical formula to assess whether a person has a healthy body weight in relation to their height. The formula divides a person's weight by the square of their height to produce a single number that indicates their body mass category.
Metric Formula
BMI = weight (kg) ÷ height² (m²)
Imperial Formula
BMI = 703 × weight (lb) ÷ height² (inches²)
The calculator automatically handles the unit conversion and mathematical calculations, providing instant results. It's important to note that while BMI is a useful screening tool, it's not a diagnostic measure and doesn't directly measure body fat or overall health.
BMI results are categorized into four main ranges that indicate different weight status classifications. Understanding your BMI category can help you assess your weight-related health risks and make informed decisions about your health.
BMI Categories
- Underweight: BMI less than 18.5
- Normal weight: BMI between 18.5 and 24.9
- Overweight: BMI between 25 and 29.9
- Obese: BMI of 30 or greater
While these categories provide general guidelines, it's essential to remember that BMI is just one of many factors that determine overall health. Athletes with high muscle mass, elderly individuals, and people of certain ethnicities may need different interpretations of their BMI results.
1. What is a healthy BMI range?
A BMI between 18.5 and 24.9 is considered healthy for most adults. However, this range may not be appropriate for all body types, ages, or ethnicities. Some health organizations recommend different ranges for specific populations.
2. Can BMI be misleading?
Yes, BMI has limitations. It doesn't distinguish between weight from muscle and weight from fat. Athletes or muscular individuals might have a high BMI but not be overweight. Similarly, elderly people might have a healthy BMI but still have too much body fat.
3. How often should I check my BMI?
For most adults, checking BMI once or twice a year is sufficient unless you're actively monitoring weight changes. If you're on a weight management program, you might want to check more frequently, but focus more on trends than individual measurements.
4. Should children use this BMI calculator?
No, this calculator is designed for adults. Children and teens should use age- and sex-specific BMI calculators, as their healthy ranges vary significantly with age and gender. Consult a pediatrician for proper child growth assessment.
5. What is the scientific source for this calculator?
This BMI calculator uses the standard formula developed by Adolphe Quetelet in the 1830s and adopted by the World Health Organization (WHO). The BMI classifications and ranges are based on WHO's global database and extensive epidemiological studies that have shown correlations between BMI ranges and health outcomes. The National Institutes of Health (NIH) and Centers for Disease Control and Prevention (CDC) have validated these ranges through numerous studies, establishing them as reliable indicators for weight-related health risks in adult populations.