MEDICINE · FREE TOOL
Adult BMI calculator
Calculate adult BMI with unrounded screening categories.
Your inputs
Enter your values, then calculate.
Decimal-point numbers; displayed rounding does not change internal values. Calculations stay on this device.
YOUR RESULT
Make the numbers clear.
Save calculation JSON ↓Calculation breakdown
Scroll sideways to see every column. You can also focus the table and use the arrow keys.
How this calculation works
BMI = kilograms ÷ meters². CDC adult categories apply from age20. BMI is a screening measure rather than a diagnosis or a measure of body fat. Do not apply adult categories to children or use this tool to assess pregnancy.
Reference: method and limitations. Method reviewed October 22, 2026.
Check the assumptions
Health calculations are educational estimates and do not replace a clinician’s assessment. Your inputs and individual circumstances can materially change how useful an estimate is.