| Skin depth | The relative lightness or darkness of the visible skin tone, measured or categorized according to the analyzer’s own scale. | Foundation, concealer, tinted moisturizer, and other complexion products. | Helps narrow the shade range before testing, reducing reliance on broad labels such as “light” or “deep.” |
| Undertone | Subtle color characteristics that may be described as warm, cool, neutral, or with another device-specific classification. | Foundation, concealer, blush, and lip color. | Provides an additional shade-matching cue. Buyers can still compare products on the skin because formulas and shade labels vary. |
| Color variation across the face | Differences in visible color between measured areas, such as the cheek, forehead, and jawline. | Foundation and concealer placement or shade selection. | Shows why a single measurement may not represent the whole face and can guide where to test a product for a natural-looking match. |
| Surface redness or uneven-looking color | Visible color differences in the measured area; this is a color observation, not a medical diagnosis. | Color correctors, complexion products, and products intended to even the appearance of skin tone. | Helps shoppers identify areas they may want to cover or balance without assuming the cause of the color difference. |
| Contrast between skin and product shades | The visual difference between a person’s skin and a selected makeup shade or color family. | Blush, bronzer, highlighter, lipstick, and eye makeup. | Supports more informed comparisons of subtle versus high-contrast color choices; personal preference remains important. |
| Visible white cast in a sunscreen sample | How noticeable a tested sunscreen appears on the user’s skin after application and settling. | Sunscreen and makeup products that include sun protection. | Can help buyers compare finish and appearance. Skin tone analysis does not determine the level of sun protection a person needs. |
| Repeatability of readings | Whether measurements remain similar when taken again under consistent conditions. | Any shade-matching or color-comparison decision. | Encourages buyers to treat a result as a useful estimate and retest if lighting, camera settings, or skin preparation changes. |