BMI Calculator
Body mass index
- BMI
- —
- Category
- —
How to use BMI Calculator
- Enter your height and weight (metric or imperial).
- Your BMI calculates instantly, along with the standard BMI category (underweight/normal/overweight/obese).
Limitations
- BMI is a population-level screening measure — it doesn't account for muscle mass, body composition, age, or sex, and isn't a diagnosis. Athletes and very muscular people commonly show as 'overweight' despite low body fat.
About this tool
BMI Calculator is a single-purpose utility on instant.tw, a free toolbox of calculators, converters, generators, and quick lookups. Everything works in your browser — nothing is uploaded, nothing is stored on a server unless explicitly noted.
Category: Health & Fitness. Browse more Health & Fitness tools.