Explore waist size through the geometry of body shape.
Conicity Index
—Valdez model · Male comparison
Enter valid measurements.
Your index in context
Pitanga & Lessa, 2004 · adults aged 30–74 in Salvador, Brazil
From cylinder to double-cone geometry
Schematic model, not a scan or measured visceral fat.
Text summary · PDF in member tools
Step-by-step calculation
The Valdez calculation
C = waist (m) ÷ [0.109 × √(weight (kg) ÷ height (m))]
Frequently asked questions
What does the conicity index measure?
It compares measured waist circumference with the circumference of an idealized cylinder based on height and weight. Higher values indicate a larger waist relative to that model. It is an anthropometric proxy, not a scan of abdominal fat.
Why do study cutoffs differ?
Thresholds depend on the study population, ages and outcome being predicted. The selected 1.25 male and 1.18 female values come from Pitanga and Lessa (2004), studying coronary-risk discrimination in adults aged 30–74 in Salvador, Brazil. They are not universal diagnostic limits.
Does biological sex change the calculation?
No. The Valdez equation uses waist, weight and height only. The sex selection changes which study comparison cutoff is displayed; it does not change the calculated index or cylinder reference.
Can this measure visceral fat directly?
No. The result does not distinguish visceral from subcutaneous fat or measure either amount directly. Health assessment requires clinical context and, when appropriate, other measurements.
What do 1.00 and √3 mean?
They are reference values for idealized shapes: a cylinder and a symmetric double cone under the geometric model. They are not hard biological limits. This tool keeps the actual calculated value even when outside that interval and extends the gauge rather than capping the result.
How should I measure my waist?
Use a consistent documented waist-measurement protocol with the tape horizontal and snug without compressing the skin. Research studies may use different anatomical sites; changing the site can change the result and its comparability. The photograph is illustrative, not a validated measurement protocol.
What does the Conicity Index calculate?
It calculates waist (m) divided by [0.109 × sqrt(weight (kg) / height (m))]. Enter waist and height in cm or inches and weight in kg or pounds; conversion to metric base units is automatic.
Which values should I enter?
Enter waist circumference, weight and height in the selected units. Choose a sex only for the study-cutoff comparison. You do not need to enter waist or height in meters.
What formula does this calculator use?
C = waist (m) / [0.109 × sqrt(weight (kg) / height (m))]. The square root covers the entire weight-to-height ratio. The same equation is used for both sexes.
Why might my result differ from another source?
Check units, waist-measurement site, the square root and rounding. Also distinguish the calculated index from study-specific classifications; different thresholds can produce different comparison labels for the same index.
Does the result update automatically?
Yes. Inputs recalculate the score, cylinder reference, gauge, schematic and worked steps. Unit switches preserve the underlying measurements. Invalid entries clear previous calculated results.
Sources & references
References inform the content; no institutional endorsement.
