BMI Calculator
Find out your Body Mass Index in seconds — free, no sign-up needed.
Enter your height and weight to see your BMI.
What is BMI?
Body Mass Index compares your weight to your height: BMI = weight(kg) ÷ height(m)². For adults, 18.5 to 24.9 is generally considered the healthy range, 25–29.9 overweight, and 30+ obese.
BMI does not measure body fat directly — athletes with high muscle mass often score “overweight” while being perfectly healthy, and healthy ranges can shift slightly by ethnicity. Treat it as a screening signal, not a verdict.
What to do with your result
If your BMI sits outside the healthy band, the sustainable response is a modest calorie adjustment, not a crash diet. Find your daily target with the calorie calculator, see the weight range behind the math in the ideal weight calculator, and aim for 0.25–0.5 kg of change per week.
Frequently asked questions
What is a healthy BMI?
For most adults, 18.5–24.9. Below 18.5 is underweight; 25–29.9 overweight; 30 and above obese. Muscle mass, frame, and ethnicity shift what is right for an individual.
Is BMI accurate for muscular people?
No — BMI cannot tell muscle from fat, so muscular athletes often read as overweight. Waist measurements and body-fat estimates give a fuller picture.
How quickly can I safely change my BMI?
Through 0.25–0.5 kg of weight change per week — roughly a 250–500 kcal daily deficit or surplus. Faster usually means losing muscle and rebounding.
Should I use metric or imperial?
Either — the calculator supports both. The formula is identical; imperial just multiplies by 703 to convert units.
This tool provides general estimates, not medical advice. Consult a professional before major dietary changes.
Ready to act on your number?
MyNutriRise tracks your meals, workouts, and progress — snap a photo and AI does the logging.