BMI Calculator

A BMI Calculator figures out your Body Mass Index by looking at your height and weight. It gives you a number that shows if your weight is in a healthy range for your height. Doctors use this as a quick screening tool, though it doesn't measure body fat directly.

The calculator divides your weight by your height squared. If you use metric, that's kilograms divided by meters squared. For imperial units, it's pounds divided by inches squared, then multiplied by 703. Pretty straightforward math that gives you a single number to work with.

Under 18.5 means underweight, 18.5 to 25 is normal weight, 25 to 30 is overweight, and over 30 is considered obese. These ranges come from the World Health Organization and help identify potential health risks related to weight.

Not really. BMI works okay for average adults but doesn't account for muscle mass, bone density, or body composition. Athletes with lots of muscle might show up as overweight. Older adults, children, and pregnant women need different assessments. It's just one tool, not the whole picture.

Yes, completely free. No account needed, no payments, nothing. Use it whenever you want from your phone, tablet, or computer. Calculate BMI as many times as you need without any restrictions.

Yes, you can switch between metric (kilograms and centimeters) and imperial (pounds and inches) units. Pick whichever system you're comfortable with and the calculator handles the conversion automatically.

If your BMI is outside the normal range, it might be worth talking to a doctor, but don't panic. BMI is just a screening tool. Your doctor can do proper assessments that consider your overall health, medical history, and other factors BMI doesn't measure.

This calculator is designed for adults. Kids and teens need special BMI-for-age charts because their bodies are still growing. If you need to check a child's BMI, look for a pediatric BMI calculator or talk to their pediatrician.

Most people check it every few months if they're tracking weight changes. If you're working on fitness goals, maybe once a month. There's no strict rule though. Just remember that daily fluctuations in weight are normal and don't mean much for BMI.

Yes, works great on all devices. Whether you're using a smartphone, tablet, or computer, the calculator adjusts to your screen and works smoothly. Check your BMI anytime, anywhere you have internet access.

The FileToConvert Advanced Calculators page has more useful tools. We've got calculators for age, GPA, percentages, averages, and various finance stuff too. Check them out if you need help with other calculations.

Generally, 18.5 to 25 is considered healthy for most adults. But this varies by age, gender, ethnicity, and individual factors. Some people are naturally healthier at slightly higher or lower numbers. Best to discuss your ideal range with a healthcare provider.

Got questions or feedback about our calculators? Want to suggest new features? Just send us a message through our contact page. We read everything and try to respond to everyone who reaches out.