BMI calculator
BMI Calculator for Adults by Height and Weight
Calculator
Choose your input units
Classification settings
Adult settings
Adult BMI result
Body mass index
BMI = 23.6
Reference data
How this calculator chooses a BMI standard
Adult BMI starts from the WHO international reference. When a selected country or region has an added adult standard, that local standard becomes the primary result and WHO remains available as comparison.
Current local adult references include United States CDC, China CDC, Taiwan HPA, Hong Kong CHP, Japan JASSO, Korea KSSO, Singapore HealthHub, India adult BMI, UK NICE, Australia, Canada, and Sri Lanka.
Pregnancy and lactation switch the result to BMI value only. The calculator keeps the number visible while treating these periods apart from the usual adult category display.
Child and teen mode uses pediatric references. United States results use CDC BMI-for-age for ages 2-19, while the global route uses WHO BMI-for-age for ages 5-19.
For children under 5, the page keeps the BMI value separate because WHO weight-for-height or weight-for-length is the more appropriate growth assessment route.
If a country is not listed, the calculator uses the WHO international adult reference until a verified local adult standard is added.
Version v0 update notes
More detailed country and regional standards
Based on the WHO international reference, this version adds more detailed regional BMI standards, including CDC, China CDC, HPA, JASSO, KSSO, NICE, Health Canada, HealthHub, India adult BMI, and Australia government adult BMI.
Pregnancy and lactation handling
For female users, pregnancy and lactation are covered as separate reference states. The calculator keeps the BMI value visible, and the result changes to a value-only view for these special periods.
Child and teen BMI mode
Child and teen mode adds more accurate BMI calculation data for younger ages. It uses age in years and months plus chart sex, then reads the result through CDC BMI-for-age or WHO BMI-for-age data where the age range applies.
How It Works
BMI formulas in standard and metric units
The calculator supports both common input systems. Each tab feeds the same underlying height and weight values, so the BMI result stays consistent.
Standard formula
Convert the height entry to total inches, then multiply the pounds-based fraction by 703.
Metric formula
Convert centimeters to meters first, then divide kilograms by height in meters squared.
Examples
Worked examples
These examples match the expected outputs for the first version of this tool.
Example 1: 5 ft 9 in and 160 lb
Example 2: 175 cm and 72 kg
Sources
Reference links
These sources define the adult BMI calculator framing and category ranges used on this page.
FAQ
Frequently asked questions
Which BMI standard does this calculator use?
The global option starts from the WHO adult BMI reference. When a supported country or region is selected, that local adult standard becomes the primary result and the WHO result remains available for comparison.
Why are there country and region choices?
Some public-health references use different BMI bands or risk points. The selector covers added local references such as CDC, China CDC, HPA, JASSO, KSSO, NICE, Health Canada, HealthHub, India adult BMI, Australia, and Sri Lanka.
How does child and teen BMI work?
Child and teen mode uses age in years and months plus chart sex, then reads the result through pediatric references. United States results use CDC BMI-for-age for ages 2-19; the global route uses WHO BMI-for-age where the age range applies.
What happens for pregnancy or lactation?
Pregnancy and lactation are handled as separate states. The calculator keeps the BMI value visible, but the adult weight-status category is treated separately for those periods.
Does BMI measure body fat directly?
No. BMI is calculated from height and weight. It is useful as a screening number, but it does not measure body fat, muscle mass, bone density, waist size, or clinical risk by itself.
When should I use the body visualizer?
Use this BMI page for the number, category, and standard comparison. Use the body visualizer when you want to see height, weight, chest, waist, hips, and inseam changes on a 3D body preview.