BMI Calculator
A population screen, not a diagnosis — but still the fastest way to put height and weight into context.
Read the maths behind this tool: BMI Formula: What the Number Means and Where It Fails
What it measures
Weight divided by height squared. Designed for populations, and it ignores body composition entirely.
Where it still helps
As a first flag. South Asian guidance often uses a lower upper bound (around 23) because metabolic risk rises at lower BMIs.
Is BMI accurate for athletes?
No — muscle is denser than fat, so athletes routinely read as overweight.
What is a healthy BMI?
18.5–24.9 on the WHO scale.