Waist-to-Height Ratio Calculator
Calculate your waist-to-height ratio (WHtR) as a quick screening measure for central adiposity and cardiometabolic risk. A common rule of thumb is to keep waist below half your height.
A Body Shape Index (ABSI) Calculator
Calculate your A Body Shape Index (ABSI) from waist circumference, height, and weight, plus a rough reference z-score for educational comparison.
⚠️ Medical Disclaimer: This calculator is for educational use only. The raw ABSI formula is standard, but the z-score and category layer on this page are rough reference estimates and should not be treated as a medical diagnosis or a definitive mortality prediction.
years
cm
kg
cm
ABSI Reference Category
Very Low Risk
ABSI = 0.07728 | Z-score = -0.95
Very LowLowAverageHighVery High
ABSI⧉
0.07728
A Body Shape Index (allometric)
ABSI Z-Score⧉
-0.95
Standard deviations from population mean
Reference Category⧉
Very Low Risk
Rough waist-for-size reference: Below average
BMI⧉
26.1
Overweight
BSA⧉
1.96 m²
Body surface area (Du Bois)
Waist-to-Height Ratio⧉
0.514
Elevated (≥0.5)
| Z-Score Range | Risk Category | Mortality Risk |
|---|---|---|
| ≤ -0.868 | Very Low | Below average |
| -0.868 to -0.272 | Low | Below average |
| -0.272 to 0.229 | Average | Average |
| 0.229 to 0.798 | High | Above average |
| > 0.798 | Very High | Significantly elevated |
| Metric | Value | Reference |
|---|---|---|
| ABSI | 0.07728 | Population mean ~0.0800 |
| BMI | 26.1 kg/m² | Normal: 18.5–24.9 |
| Waist-Height Ratio | 0.514 | Target: <0.50 |
| BSA | 1.96 m² | Average: 1.7–1.9 m² |
Planning notes, formulas, and examples
About the A Body Shape Index (ABSI) Calculator
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.
When This Page Helps
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.
How to Use the Inputs
- Select sex and enter age.
- Enter height, weight, and waist circumference.
- Review the raw ABSI value first.
- Use the z-score and category only as a rough educational reference rather than a clinical prediction.
- Compare the result with BMI and waist-to-height ratio for context.
Formula used
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.Example Calculation
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.
Tips & Best Practices
- Treat the raw ABSI value as the main output.
- Use the reference z-score cautiously unless you know the source population behind it.
- Compare repeated measurements taken the same way rather than overreacting to one reading.
- Waist-to-height ratio remains a simple companion measure.
- ABSI is descriptive, not diagnostic.
- Use the result alongside the broader cardiometabolic picture.
What ABSI Adds
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.
What It Does Not Do
ABSI does not directly measure visceral fat, and it does not replace imaging, metabolic testing, or full cardiovascular risk assessment.
Best Use
Use ABSI as an extra descriptive anthropometric measure rather than as a stand-alone medical risk verdict.
Sources & Methodology
Last updated:
Methodology
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.
Sources
- A New Body Shape Index Predicts Mortality Hazard Independently of Body Mass Index (PLOS ONE)
- National Health and Nutrition Examination Survey (Centers for Disease Control and Prevention) — Reference dataset used in the original ABSI derivation paper.
Frequently Asked Questions
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.
More in this topic
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BMI Calculator
Calculate your Body Mass Index (BMI), see your WHO weight category, healthy weight range for your height, and understand what your BMI means for your health.