Body Roundness Index Calculator
Calculate body roundness index from height and waist circumference with health interpretation.
What Is Body Roundness Index?
Body roundness index (BRI) estimates how round the body silhouette is from height and waist circumference. It is an alternative to BMI when abdominal fat distribution matters. Compare with A Body Shape Index Calculator and BMI Calculator.
BRI Formula
$$\text{BRI} = 364.2 - 365.5 \times \sqrt{1 - \frac{\left(\frac{WC}{2\pi}\right)^2}{(0.5 \times h)^2}}$$
Waist circumference and height must be in meters. Higher BRI generally reflects more central roundness.
How to Measure Waist
Measure at the midpoint between the lowest rib and the top of the iliac crest at the end of a normal exhale. Keep the tape horizontal and snug without compressing the skin.
Frequently Asked Questions
Is BRI better than BMI?
BRI considers waist size, so it may better reflect central adiposity. Neither replaces a full medical assessment.
What BRI is considered healthy?
Research often highlights a lower-risk range around 3.41 to 5.45, but interpretation should be individualized.
Can athletes have high BRI?
Very muscular people with thick trunk musculature may measure a larger waist without excess visceral fat.
What units should I use?
Enter height and waist in centimeters. The calculator converts internally to meters for the formula.
Related Tools
Hex to Pantone Converter
JSON To JSDoc
Countdown Calculator
301 Redirect Code Generator
Epoch & Unix Timestamp Converter
Text Replacer
Sort Graphemes
Pitch Diameter Calculator
XML Pretty Print
Lighting Calculator
Concrete Weight Calculator
Domain and Range Calculator
YAML to Dart POJO Generator
SHA-2 Hash Generator
Area Calculator
Time Card Calculator
Pounds to Kilograms Converter
Mean Sac Diameter Calculator
Absence Percentage Calculator
Carrying Capacity Calculator