BMI Calculator
Calculate your Body Mass Index (BMI) precisely to check if your weight is optimal for your height.
Enter your stats to reveal your body mass index.
What Is BMI and Why Does It Matter?
Body Mass Index (BMI) is a simple calculation that uses your height and weight to estimate whether you are at a healthy weight. It was developed by Belgian mathematician Adolphe Quetelet in the 1830s and remains one of the most widely used screening tools in healthcare worldwide.
The formula is straightforward: BMI equals your weight in kilograms divided by the square of your height in meters (kg/m2). Our calculator above handles the math for you in both metric and imperial units.
How to Interpret Your BMI Results
A BMI between 18.5 and 24.9 is considered healthy for most adults. Below 18.5 suggests you may be underweight, while 25 and above indicates excess weight that could increase your risk of health problems including heart disease, Type 2 diabetes, high blood pressure, and certain cancers.
However, BMI is not a perfect measure. It does not distinguish between muscle and fat, so very muscular people may have a high BMI despite being healthy. It also does not account for fat distribution - carrying weight around your midsection (visceral fat) is more dangerous than carrying it in your hips and thighs.
BMI Limitations You Should Know
While BMI is a useful starting point, it has several limitations. It does not account for age (older adults naturally have more body fat), gender (women typically have more body fat than men at the same BMI), muscle mass (athletes may be classified as overweight), or ethnicity (research shows health risks may begin at different BMI thresholds for different populations). For example, the WHO suggests that people of South Asian, Chinese, and Japanese descent may face increased health risks at a BMI of 23 or above, rather than 25.
For a more complete picture of your health, consider measuring your waist circumference as well. A waist measurement above 40 inches (102 cm) for men or 35 inches (88 cm) for women indicates a higher risk of obesity-related conditions, regardless of BMI.
Tips for Reaching a Healthy BMI
If your BMI falls outside the normal range, small sustainable changes can make a big difference. Focus on eating whole, nutrient-dense foods rather than crash dieting. Aim for at least 150 minutes of moderate exercise per week. Get 7-9 hours of sleep per night, as poor sleep disrupts hormones that control appetite. Manage stress, which can lead to emotional eating. And most importantly, work with a healthcare provider who can give you personalized advice based on your complete health picture.
Disclaimer: This BMI calculator is for educational purposes only. BMI is a screening tool, not a diagnostic measure. Consult your healthcare provider for a comprehensive health assessment.