⚕️ For clinical reference only. Not a substitute for professional judgment.

BMI Body Mass Index

Body mass index with WHO classification. Bariatric surgery threshold (BMI ≥40, or ≥35 with comorbidities) shown automatically.

Enter values
Awaiting weight and height.

Units

Metric

kg
cm
WHO Classification
<18.5 = Underweight
18.5–24.9 = Normal
25.0–29.9 = Overweight
30.0–34.9 = Obese Class I
35.0–39.9 = Obese Class II
≥40.0 = Obese Class III (morbid)

Bariatric surgery: ≥40, or ≥35 + comorbidities
References
  • WHO Expert Consultation. Lancet. 2004.
  • NICE CG189 — Obesity: identification, assessment and management. 2014 (updated 2023).
  • BOMSS Guidelines — Bariatric surgery. 2022.