Calculate your A Body Shape Index (ABSI) from waist circumference, height, and weight, plus a rough reference z-score for educational comparison.
The A Body Shape Index (ABSI) Calculator estimates ABSI and a rough reference z-score from waist circumference, height, weight, age, and sex. It is designed to add information about body shape and fat distribution that BMI does not capture.
ABSI was developed by Krakauer and Krakauer using NHANES data. Higher values indicate greater central adiposity relative to body size in population studies. This calculator also shows related measures such as BMI, body surface area, and waist-to-height ratio for context, but its z-score categories should be treated as approximate reference labels rather than a stand-alone prognosis model.
BMI alone does not describe how body fat is distributed. Two people with the same BMI can have different anthropometric profiles if one carries more abdominal fat.
ABSI can be used alongside BMI as an additional descriptive measure, but it should be read as a screening and comparison tool rather than as a diagnosis on its own.
ABSI = WC / (BMI^(2/3) × Height^(1/2)) Where: - WC = waist circumference in meters - BMI = weight / height² in kg/m² - Height in meters The raw ABSI formula is standard. The z-score shown on this page is a rough reference estimate and should not be treated as a clinical mortality model without a published age- and sex-specific reference dataset.
Result: ABSI 0.07834, reference z-score -0.33
For a 45-year-old male with height 175 cm, weight 80 kg, and waist circumference 90 cm, the raw ABSI is 0.07834. The page also shows a rough reference z-score, but the raw ABSI is the more defensible output.
ABSI tries to isolate waist size relative to height and BMI, giving an additional way to describe central body shape. That can be useful when BMI alone misses an important difference in abdominal adiposity.
ABSI does not directly measure visceral fat, and it does not replace imaging, metabolic testing, or full cardiovascular risk assessment.
Use ABSI as an extra descriptive anthropometric measure rather than as a stand-alone medical risk verdict.
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This page computes the raw ABSI formula from waist circumference, BMI, and height, then supplements it with a site-defined z-score-style reference display for rough comparison. The raw ABSI calculation follows the original allometric form; the extra category layer is best treated as an educational reference rather than a validated mortality model for every population.
Because age- and sex-specific ABSI reference distributions vary by dataset, the page should not present its category labels as a clinical diagnosis or a definitive survival estimate. The raw ABSI value is the most defensible output; any higher-level risk interpretation should be read cautiously and alongside the rest of the cardiometabolic picture.
BMI only considers height and weight, while ABSI also incorporates waist circumference to reflect central adiposity relative to body size.
There is no single universally correct cutoff for every population. ABSI is best interpreted in context rather than as a simple “good” or “bad” threshold.
Measure at a consistent abdominal landmark with a flexible tape after a normal exhale. Consistency matters more than tiny one-time differences.
Like other anthropometric indices, it is a simplification. It is less useful than direct imaging when body composition needs to be measured precisely.
Reducing waist circumference relative to body size generally lowers ABSI. In practice, that usually means the same lifestyle measures used to improve overall cardiometabolic health.
No. ABSI is better used alongside BMI and waist-to-height ratio than as a complete replacement.