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Longevity

Body Adiposity Index (BAI) Calculator

Unlike BMI, the Body Adiposity Index estimates body fat percentage directly from hip circumference and height — without requiring body weight. Validated across diverse populations including African American and Hispanic cohorts.

Your Measurements

Measure at the widest point of your hips and buttocks.

Used for age-adjusted interpretation of results.

Your Result

📊

Enter your height and hip circumference to estimate body fat via the BAI formula.

📋 What Your Result Means

For educational purposes only — not medical advice.

The gauge above shows your estimated body fat percentage based on the BAI formula. The key advantage of BAI is that it does not require a scale — only a tape measure for hip circumference and your height.

Accuracy considerations: BAI has a standard error of roughly 4 to 5 percentage points compared to DEXA scans. It tends to overestimate body fat in lean individuals and underestimate it in those with higher body fat. It is less accurate than skinfold calipers or the Navy body fat method for most populations.

Population note: BAI was validated primarily in Mexican-American and Black populations (the BetaGene and TARA cohorts in Bergman et al. 2011). Subsequent validation studies found reduced accuracy in Caucasian and Asian populations. If you fall outside the original study demographics, treat this result as a rough estimate and cross-check with our Navy Body Fat calculator.

BAI also does not distinguish between subcutaneous and visceral fat. For cardiovascular risk assessment, the Waist-to-Hip Ratio or Visceral Fat calculators may be more informative.

BAI = (Hip circumference cm / height m^1.5) − 18
Bergman RN et al. — A Better Index of Body Adiposity (2011)
Obesity Journal · DOI: 10.1038/oby.2011.38 · n = 1,733 subjects (BetaGene & TARA cohorts)

Limitations

BAI was validated primarily in Hispanic and African American populations and may be less accurate for other ethnic groups. It does not account for body composition — muscular individuals with large hips may receive a higher BAI than their actual body fat warrants.

~ Moderate Evidence

Want to learn more? Read our in-depth article: Body Adiposity Index vs BMI: Which Is More Accurate? →

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🤝 Amazon-Partner: Als Amazon-Partner verdiene ich an qualifizierten Verkäufen. · As an Amazon Associate, I earn from qualifying purchases.

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