Calculate your Body Mass Index. Metric and imperial units; six classification standards — WHO, China, Japan (JASSO), Asia-Pacific (WPRO), US (CDC/NIH), and UK (NHS).
Enter your height and weight in either metric (cm / kg) or imperial (ft+in / lb) units. Your BMI updates instantly along with the category, the healthy weight range that corresponds to your height, and a colored scale that adapts to the chosen standard.
Six standards are available — switch between them to compare:
- WHO — international reference; Normal 18.5–24.9, Overweight 25–29.9, Obese class I/II/III at 30/35/40.
- China — stricter Asian cutoffs used in domestic guidelines; Normal 18.5–23.9, Overweight 24–27.9, Obese ≥ 28.
- Japan (JASSO) — anything ≥ 25 is “obese”; graded 1°–4° at 25 / 30 / 35 / 40.
- Asia-Pacific (WPRO) — overweight already at 23, used by India, Singapore, Malaysia and others.
- US (CDC/NIH) — labels healthy weight, then obesity class 1/2/3 at the same WHO thresholds.
- UK (NHS) — merges 30–39.9 as just “obese” and labels ≥ 40 as severely obese.
BMI is a screening indicator, not a diagnosis. It does not distinguish muscle mass from fat — athletes and very muscular individuals may register as “overweight” without elevated health risk. All calculations happen locally in your browser.