BMI Calculator
Calculate body mass index and learn about the standard adult screening categories. BMI does not directly measure body fat or diagnose your health.
Your numbers.
Your starting point.
Enter your details and calculate to see your estimate, what it means and how to use it.
How this calculator works
BMI = weight in kilograms ÷ height in metres squared. General adult categories are below 18.5 (underweight), 18.5 to below 25 (healthy weight range), 25 to below 30 (overweight), and 30 or above (obesity range). These are screening labels, not descriptions of your worth or a diagnosis. Health risks may arise at lower BMI in some ethnic backgrounds; this tool does not make ethnicity-specific assessments.
What your result means
Your result places a height-and-weight ratio in a general adult screening category. It does not tell you how much body fat you have or establish whether you are healthy. Interpret it alongside other information with an appropriate professional.
What to do next
- Read the BMI limitations before interpreting the category.
- Use health information beyond your weight and height.
- Ask a healthcare professional if you are unsure what the result means for you.
Frequently asked questions
Can BMI tell me my body fat percentage?
No. It cannot distinguish fat, muscle and bone or show where fat is stored. Waist measurements and other health information can add context.
Who should not rely on this tool?
It is for adults and is unsuitable during pregnancy. High muscle mass, some medical conditions and individual backgrounds affect interpretation. Use a clinician for a personal assessment.
Methodology & sources
General educational information for adults. Estimates are not a diagnosis or a personalised diet. For pregnancy, breastfeeding, eating-disorder concerns, medical conditions or medication-related questions, seek qualified guidance. Read the full disclaimer.