Waist-to-Hip / Waist-to-Height Ratio implementation

Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

Record owner

Guth Instruments

Lifecycle

verified-clean

Evidence ID

t3-014

Effect

Computation or source lookup only

Input and validation requirements

The specification exposes undefined results when hip or height is zero, does not define the risk-band threshold table or branch conventions, and leaves unit normalization unspecified; mixed units can therefore produce a numerically valid but physically nonsensical WHtR.

Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

{
  "inputs": {
    "waist": 80,
    "hip": 100,
    "height": 170,
    "unit": "cm"
  },
  "expected_outputs": {
    "WHR": 0.8,
    "WHtR": 0.4705882353,
    "risk_band_label": null
  },
  "working": "WHR = waist / hip = 80 / 100 = 0.8. WHtR = waist / height = 80 / 170 = 8 / 17 = 0.4705882353. Risk band = undetermined because no threshold table or mapping is supplied."
}

Other records

Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

• VERIFIED_LEDGER.json
• evidence-tranche3/tranche3-results.json