> For the complete documentation index, see [llms.txt](https://docs.saas.haut.ai/haut.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.saas.haut.ai/haut.ai/haut.ai-features/algorithms/face-skin-analysis-3-0/lines/lip-lines.md).

# Lip Lines

What the Lip Lines parameter measures around the mouth, why perioral lines form, and how to read the grades it returns.

## About Parameter

Lip lines (also known as perioral lines or smoker's lines) are fine wrinkles that radiate outward from the mouth, encircling the lips around their entire perimeter. They form due to repeated movement of the orbicularis oris muscle — during speaking, smiling, drinking, and similar activities — and become more pronounced over time as collagen production declines and skin elasticity decreases. Habits such as smoking and prolonged sun exposure can make these lines appear earlier and become more prominent.

## Features

1. Works with 1 and 3 side facial images.
2. Evaluates severity (grade) of lip lines.
3. Separates and segments deep and fine lines.

## Output

1. Grade from 1 to 5.
2. Vector mask for deep lines.
3. Vector mask for fine lines.
4. Vector mask containing both deep lines and fine lines.
5. Algorithm-assigned skin condition tag (Great, Good, Average, Poor).
6. Amount of lines.
7. Amount of deep lines.
8. Amount of fine lines.
9. Length of lines relative to length of the perioral area.
10. Length of deep lines relative to length of the perioral area.
11. Length of fine lines relative to length of the perioral area.

Note: When a single line has varying severity (containing both deep and fine sections), it is categorized as one deep line rather than a fine line.

## Grades Description

Severity assessment based on the depth and extent of the most prominent wrinkles.

<table><thead><tr><th width="120.4296875">Grade value</th><th width="484.68359375">Description</th><th>Tags</th></tr></thead><tbody><tr><td>1</td><td>Wrinkles are absent; however, skin texture irregularities related to dryness or non-target wrinkles may be observed.</td><td>Great</td></tr><tr><td>2</td><td>Fine wrinkles are appearing; they may be barely noticeable, and there are no deep wrinkles.</td><td>Good</td></tr><tr><td>3</td><td>Fine wrinkles are clearly discernible, and deep wrinkles are beginning to appear; however, the deepest part is surrounded by "fine" wrinkles, and the wrinkle ridge (or border) is weakly pronounced.</td><td>Average</td></tr><tr><td>4</td><td>The wrinkles are deepening further and are clearly visible along their entire length, though they may not be deep throughout; the wrinkle ridge (or border) is pronounced.</td><td>Poor</td></tr><tr><td>5</td><td>The wrinkle ridge is well-defined, and the wrinkles possess noticeable depth.</td><td>Poor</td></tr></tbody></table>

## Algorithm API

{% hint style="warning" %}
API access is available only for <mark style="color:purple;">**Professional**</mark> plan clients
{% endhint %}

See [Lip Lines Parameter Result Scheme](/haut.ai/developers/saas-api-overview/api-for-face-skin-analysis-3.0/lines/lip-lines.md).

***

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{% endhint %}

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---

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