Calculate BRI from height and waist circumference using the Thomas ellipse formula.
| BRI | – |
Use this calculator for body roundness index. BRI = 364.2 − 365.5 × √(1 − (waist / 2π)² / (0.5 × height)²), with waist and height in the same length unit. The ratio is dimensionless, so centimetres or inches both work if they match. Combinations that would make the term under the square root non-positive are rejected.
Height and waist can be entered in centimetres (cm) or inches (in).
Height: Standing height, in cm or in.
Waist: Waist circumference, in cm or in.
BRI: Body roundness index (dimensionless).
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