# BMI & Waist Circumference Calculator

> Classify adult weight status against the WHO BMI cut-offs, including the grades of chronic energy deficiency, with waist circumference and waist-to-height ratio.

Source: https://www.medicine.et/tools/bmi-calculator  
Site: Bloom Medicine — https://www.medicine.et

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## What it calculates

- Body mass index, classified against the WHO international cut-offs — severe, moderate and mild thinness (chronic energy deficiency grades III to I), normal weight, overweight, and obesity classes I to III.
- The same BMI against the 2004 WHO Asian cut-offs, where overweight starts at 23 and obesity at 27.5.
- The healthy weight range in kilograms for the entered height, and the distance from it.
- Central adiposity from waist circumference against the WHO action levels, and from waist-to-height ratio against the NICE bands.

## Inputs

- Weight (kg)
- Height (cm)
- Sex (waist thresholds only)
- Age, optional — flags that adult cut-offs do not apply under 20
- Waist circumference in cm, optional

## Caveats

- BMI is a screening index, not a diagnosis, and cannot distinguish fat from muscle.
- It is unreliable in pregnancy, in oedema or ascites, in people with high muscle mass, and in older adults who have lost height.
- Under 20, the WHO BMI-for-age z-score reference applies instead of these adult bands.

The calculator itself is interactive and runs in the browser at https://www.medicine.et/tools/bmi-calculator. No patient data leaves the device.