Body Roundness Index (BRI)
Body roundness index (Thomas DM, et al. Obesity 2013) = 364.2 - 365.5 x sqrt(1 - ((waist / (2·pi)) / (0.5 x height))^2), waist and height in the same units; higher = greater central adiposity.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Waist circumference
- 90 cm
- Height
- 170 cm
Result: Body roundness index 3.93 — higher = more central adiposity.
The tool opens with these values already filled in. Replace them with your own.
What the result means
- ~1-16
- 364.2 - 365.5 x sqrt(1 - ((waist/(2·pi))/(0.5·height))^2). Higher = greater central adiposity / cardiometabolic risk. An index, not a diagnosis.
What you enter
- Waist circumference
- Height
How this is calculated
Thomas DM, Bredlau C, Bosy-Westphal A, et al. Relationships between body roundness with body fat and visceral adipose tissue emerging from a new geometrical model. Obesity (Silver Spring). 2013;21(11):2264-2271. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.