--- title: "What Is Cupid's Bow Depth in FaceIQ Labs' Harmony Analysis?" description: "Cupid's Bow Depth is a front-view Harmony measurement at FaceIQ Labs: the vertical drop from the upper-lip peak to the central dip, with its formula, worked example and accuracy limits." canonical: "https://appear.faceiqlabs.com/support/harmony/cupid-s-bow-depth" --- # What Is Cupid's Bow Depth in FaceIQ Labs' Harmony Analysis? Cupid's Bow Depth is a front-view Harmony measurement in FaceIQ Labs' facial analysis. It is the vertical drop from the marked upper-lip peak to the central dip of the Cupid's bow, calculated as (central-dip y − upper-lip-peak y) × photo scale. Millimeter values are estimates based on an assumed 190 mm hairline-to-chin height. ## Key facts - Cupid's Bow Depth is a Harmony measurement taken from the mouth region of the front view. - It is the vertical drop from the marked upper-lip peak to the central dip of the Cupid's bow. - Formula: (central-dip y − upper-lip-peak y) × photo scale. - A lower value describes a shallower dip at the center of the upper lip; a higher value describes a deeper dip relative to the marked lip peak. - FaceIQ Labs scales each photo using an assumed 190 mm hairline-to-chin height, so millimeter values are estimates, not calibrated physical measurements. - Worked example: a 12-unit vertical drop at 0.2 estimated mm per unit gives 2.4 mm; this is not a target range. - FaceIQ Labs describes this as its own landmark-based description of facial shape; the linked research has not directly validated the exact formula or its score. - Makeup, a smile and asymmetric peaks can alter the apparent dip, so the natural lip border should be marked. - FaceIQ Labs' Harmony pillar uses 70+ facial ratios and angles and is weighted roughly 60% from the front photo and 40% from the side photo. ## What is Cupid's Bow Depth in FaceIQ Labs' Harmony analysis? Cupid's Bow Depth is a front-view Harmony measurement in FaceIQ Labs' facial analysis. It is the vertical drop from the marked upper-lip peak to the central dip of the Cupid's bow, taken from landmarks on the mouth in a user's front photo. It is one of the 70+ ratios and angles that Harmony uses. ## How does FaceIQ Labs calculate Cupid's Bow Depth? FaceIQ Labs calculates Cupid's Bow Depth as (central-dip y − upper-lip-peak y) × photo scale. The central dip and the upper-lip peak are landmarks on the front photo. The difference in their vertical positions is multiplied by a photo scale to give an estimated millimeter value. ## Why does Cupid's Bow Depth matter? - FaceIQ Labs includes Cupid's Bow Depth because the central dip shapes the upper-lip outline. Its depth describes a local contour that can differ even between lips with the same overall height and width. - Lower: a shallower dip at the center of the upper lip. - Higher: a deeper dip relative to the marked lip peak. ## What is the ideal range for Cupid's Bow Depth? FaceIQ Labs' Cupid's Bow Depth guide does not state a target or ideal range. Its worked example values are explicitly not a target range, and its score weights and reference ranges are described as model settings that the cited research does not validate. Across Harmony overall, ratios are compared to ideal ranges adjusted for gender and ethnicity. ## What does a worked example of Cupid's Bow Depth look like? FaceIQ Labs illustrates Cupid's Bow Depth with this example: a 12-unit vertical drop at 0.2 estimated mm per unit gives 2.4 mm. The example values only explain the calculation. They are not a target range and are not measurements of the schematic shown on the guide page. ## Where does the Cupid's Bow Depth measurement come from? Cupid's Bow Depth is a FaceIQ landmark-based description of facial shape, not a formula validated by published research. The linked research gives background on facial measurement or perception but has not directly validated this exact formula or its score. FaceIQ Labs cites Gibelli et al. (2015), 'A Quantitative Analysis of Lip Aesthetics: The Influence of Gender and Aging', which measured lip area, volume and thickness across sex and age groups. It describes lip morphology and does not establish a universally attractive lip ratio. ## How accurate is Cupid's Bow Depth, and why are the millimeters approximate? FaceIQ Labs' millimeter values for Cupid's Bow Depth are estimates, not calibrated physical measurements. The platform scales the photo using an assumed 190 mm hairline-to-chin height. Results also depend on marking the natural lip border, because makeup, a smile and asymmetric peaks can alter the apparent dip. ## Which other mouth measurements does FaceIQ Labs explain? - Lip Thickness - Lower Lip to Upper Lip Ratio - Mouth-to-Nose Width Ratio - Interpupillary-Mouth Width Ratio - Mouth Corner Position - Chin-to-Philtrum Ratio ## Frequently asked questions ### What is Cupid's Bow Depth? It is a FaceIQ Labs Harmony measurement of the vertical drop from the marked upper-lip peak to the central dip of the Cupid's bow, taken from the mouth region of the front view. ### What formula does FaceIQ Labs use for Cupid's Bow Depth? (Central-dip y − upper-lip-peak y) × photo scale. ### Does a higher Cupid's Bow Depth value mean a deeper dip? Yes. A higher value describes a deeper dip relative to the marked lip peak, and a lower value describes a shallower dip at the center of the upper lip. ### Are the millimeter values for Cupid's Bow Depth exact? No. FaceIQ Labs scales the photo using an assumed 190 mm hairline-to-chin height, so the values are estimates, not calibrated physical measurements. ### What can make a Cupid's Bow Depth result less accurate? Makeup, a smile and asymmetric peaks can alter the apparent dip. The guide says to mark the natural lip border. ### Is the 2.4 mm example a target value? No. The example of a 12-unit drop at 0.2 estimated mm per unit giving 2.4 mm only explains the calculation and is not a target range. ### Has research validated FaceIQ Labs' Cupid's Bow Depth formula? No. FaceIQ Labs states that the linked research gives background on facial measurement or perception but has not directly validated this exact formula or its score. ## 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). 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