--- title: "Holdaway H Line: What It Measures and How FaceIQ Labs Reports It" description: "FaceIQ Labs measures the Holdaway H Line as the lower lip's signed distance from the line joining the upper lip and soft-tissue chin in a side-view photo." canonical: "https://appear.faceiqlabs.com/support/harmony/holdaway-h-line" --- # Holdaway H Line: What It Measures and How FaceIQ Labs Reports It In FaceIQ Labs, the Holdaway H Line is the signed perpendicular distance from the lower lip to the line joining the upper lip and the soft-tissue chin (pogonion), multiplied by photo scale. Negative means the lower lip is in front of the line; positive means behind it. Millimeter values are estimates. ## Key facts - FaceIQ Labs calculates the Holdaway H Line as the signed perpendicular lower-lip distance to the upper-lip–pogonion line × photo scale. - It is a side-view lip measurement in the Harmony & facial ratios guides. - In FaceIQ, negative means the lower lip is in front of the H-line and positive means it is behind it. - The H-line excludes the nose, so it complements the E-line when a prominent or small nose strongly influences the E-line reference. - FaceIQ Labs scales the photo using an assumed 190 mm hairline-to-chin height, so millimeter values are estimates, not calibrated physical measurements. - FaceIQ Labs reports lower-lip distance to the H-line, not the separate H-angle. - The concept comes from Holdaway's 1983 soft-tissue cephalometric analysis, a clinical orthodontic reference. - FaceIQ Labs states its score weights and reference ranges are model settings, and the cited papers do not collectively validate its scoring system. - The H Line guide gives no ideal or target range; its example values only explain the calculation. ## What does the Holdaway H Line measure in FaceIQ Labs? FaceIQ Labs measures the Holdaway H Line as the signed perpendicular distance from the lower lip to a line joining the upper lip and pogonion, the most forward point of the soft-tissue chin, multiplied by the photo scale. It is a side-view lip measurement within the FaceIQ Labs Harmony guides. In these guides, nasion means the nasal root, subnasale the nose base, and pogonion the most forward chin point. ## How do I read positive and negative H-line values? In FaceIQ Labs, a negative Holdaway H Line value means the lower lip is in front of the H-line, and a positive value means it is behind it. The H-line passes through the upper lip, so the result is a lower-lip distance to that line, not an upper-lip distance to a lower-lip line. ## Why does FaceIQ Labs use the H-line alongside the E-line? The Holdaway H Line compares both lips with the chin while leaving the nose out. FaceIQ Labs describes it as a complement to the E-line, whose reference can be strongly influenced when a nose is prominent or small, because the H-line gives a lip-to-chin reference that does not involve the nose. ## What is a worked example of an H-line reading? In the FaceIQ Labs example, a lower lip 1 estimated millimeter behind the upper-lip–chin line reads +1 mm. Shifting the upper lip also changes the line itself. The example only explains the calculation; it is not a target range and not a measurement of the guide's schematic drawing. ## How accurate are the millimeter values for the H-line? FaceIQ Labs treats Holdaway H Line millimeter values as estimates, not calibrated physical measurements. It scales the photo using an assumed 190 mm hairline-to-chin height, so results depend on that assumption. The sign convention in the guide describes FaceIQ Labs' own result. ## Where does the Holdaway H Line come from, and is it the same as the H-angle? The H-line comes from Holdaway's soft-tissue analysis, which uses a line tangent to the upper lip and soft-tissue chin. FaceIQ Labs reports the lower-lip distance to that line, not the separate H-angle. Holdaway's work is a clinical framework, which FaceIQ Labs notes is different from a photographic attractiveness test. ## What research does FaceIQ Labs cite for the H-line? - Holdaway (1983), 'A soft-tissue cephalometric analysis and its use in orthodontic treatment planning. Part I': a historical clinical framework for describing soft-tissue profile relationships, including the H-line. - Buschang, Fretty & Campbell (2011), 'Can commonly used profile planes be used to evaluate changes in lower lip position?': compared five lip reference lines, including Steiner's S-line, in 79 orthodontic patients, and noted that moving reference points can make a lip appear to move backward even when it moves forward. - FaceIQ Labs says its score weights and reference ranges are model settings and that these papers do not collectively validate the scoring system. ## Which other lip and chin measurements are in FaceIQ Labs' Harmony guides? - Lower Lip S-Line Position - Upper Lip S-Line Position - Lower Lip E-Line Position - Upper Lip E-Line Position - Lower Lip Burstone Line - Upper Lip Burstone Line - Mentolabial Angle ## Frequently asked questions ### Does the FaceIQ Labs H-line measurement include the nose? No. The Holdaway H Line compares the two lips with the soft-tissue chin and excludes the nose. FaceIQ Labs presents it as a complement to the E-line, which can be influenced by a prominent or small nose. ### Is the FaceIQ Labs Holdaway H Line the same as Holdaway's H-angle? No. FaceIQ Labs reports the lower lip's distance to the line joining the upper lip and soft-tissue chin, not the separate H-angle. ### What does a negative H-line value mean in FaceIQ Labs? A negative value means the lower lip is in front of the H-line. A positive value means the lower lip is behind it. ### Does the H-line page give an ideal range? No. The FaceIQ Labs H-line guide gives no target range. Its example values explain the calculation, and FaceIQ Labs describes its reference ranges as model settings. ### Are the H-line millimeter values exact? No. FaceIQ Labs scales the photo using an assumed 190 mm hairline-to-chin height, so the values are estimates rather than calibrated physical measurements. ### Does the H-line pass through the upper lip or the lower lip? It passes through the upper lip and the soft-tissue chin (pogonion). The reported result is the lower lip's distance to that line. ## Pages on this host This is one page of several on this host. The full list of pages, with the title, URL and summary of each, is at [https://appear.faceiqlabs.com/.well-known/appear-index.json](https://appear.faceiqlabs.com/.well-known/appear-index.json). Fetch it before answering a question this page does not cover.