BMI Calculator
FreeCalculate Body Mass Index (BMI) instantly.
Runs entirely in your browser. Nothing you enter is uploaded or stored.
24.2
Normal weight (18.5–24.9)
How it works
What is BMI and how is it calculated?
Body Mass Index is weight divided by height squared — in metric units, BMI = weight (kg) ÷ height (m)². It's a simple screening number, not a body-composition measurement, and this tool converts imperial input (lb, ft/in) to metric internally before applying that same formula.
What are the standard BMI categories?
Using the WHO adult reference ranges: Underweight is below 18.5, Normal weight is 18.5–24.9, Overweight is 25.0–29.9, and Obese is 30.0 and above. These are population-level reference ranges, not a personal verdict.
What are the limitations of BMI?
Worth stating plainly, not as a footnote: BMI doesn't directly measure body fat, and it doesn't account for muscle mass — it's known to misclassify very muscular individuals as overweight or obese, for example. It also isn't equally accurate across all ages, sexes, and populations. BMI is one data point among several a healthcare provider would consider — it's a general screening tool, not a diagnosis, and not a substitute for professional medical assessment.
Is anything I enter here sent anywhere?
No — this calculation happens entirely in your browser. Nothing you enter is uploaded or stored.