> 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/body-skin-analysis/regions-and-metrics.md).

# Regions & Metrics

The body regions Haut.AI detects, which metric reports a result for each, and how a region is told apart from noise.

This page documents which body region each metric scores, and how region detection decides what counts as a real region versus noise.

***

## How region detection works

1. **Detect & segment** — we detect skin, then segment it into regions: `Torso`, `Chest`, `Back`, `Neck`, `Face`, `Upper Arm`, `Arm`, `Hand`, `Upper Leg`, `Lower Leg`, `Foot`, `Macro`.
2. **Score per region** — each metric's algorithm then runs on the regions it applies to, where applicable (see coverage table below).
3. **Filter noise** — any region covering less than 10% of the photo's total skin is ignored.

***

## Region coverage by metric

Which regions each metric can report a per-area result for. A region still comes back `null` for a given photo if no large-enough area of that class was detected in it. Chest and Back mirror Torso coverage for every metric — wherever a metric reports a Torso result, it also reports Chest and Back.

| Metric                                                                                                          | Torso | Chest | Back | Neck | Face | Upper Arm | Arm | Hand | Upper Leg | Lower Leg | Foot | Macro |
| --------------------------------------------------------------------------------------------------------------- | ----- | ----- | ---- | ---- | ---- | --------- | --- | ---- | --------- | --------- | ---- | ----- |
| [Breakouts](/haut.ai/haut.ai-features/algorithms/body-skin-analysis/breakouts.md)                               | ✓     | ✓     | ✓    |      | ✓    |           |     |      |           |           |      | ✓     |
| [Lines](/haut.ai/haut.ai-features/algorithms/body-skin-analysis/lines.md)                                       | ✓     | ✓     | ✓    | ✓    | ✓    | ✓         | ✓   | ✓    | ✓         | ✓         | ✓    | ✓     |
| [Sagging](/haut.ai/haut.ai-features/algorithms/body-skin-analysis/sagging.md)                                   |       |       |      | ✓    |      |           |     |      |           |           |      |       |
| [Pigmentation](/haut.ai/haut.ai-features/algorithms/body-skin-analysis/pigmentation.md)                         | ✓     | ✓     | ✓    | ✓    | ✓    | ✓         | ✓   | ✓    | ✓         | ✓         | ✓    | ✓     |
| [Redness](/haut.ai/haut.ai-features/algorithms/body-skin-analysis/redness.md)                                   | ✓     | ✓     | ✓    | ✓    | ✓    | ✓         | ✓   | ✓    | ✓         | ✓         | ✓    | ✓     |
| [Uniformness](/haut.ai/haut.ai-features/algorithms/body-skin-analysis/uniformness.md)                           | ✓     | ✓     | ✓    | ✓    | ✓    | ✓         | ✓   | ✓    | ✓         | ✓         | ✓    | ✓     |
| [Barrier Impairment](/haut.ai/haut.ai-features/algorithms/body-skin-analysis/barrier-impairment.md) (`dryness`) |       |       |      |      |      |           | ✓   | ✓    |           | ✓         | ✓    | ✓     |
| [Microscaling](/haut.ai/haut.ai-features/algorithms/body-skin-analysis/microscaling.md)                         |       |       |      |      |      |           | ✓   | ✓    |           | ✓         | ✓    | ✓     |
| [Macroscaling](/haut.ai/haut.ai-features/algorithms/body-skin-analysis/macroscaling.md)                         |       |       |      |      |      |           | ✓   | ✓    |           | ✓         | ✓    | ✓     |
| [Thickening](/haut.ai/haut.ai-features/algorithms/body-skin-analysis/thickening.md)                             |       |       |      |      |      |           | ✓   | ✓    |           | ✓         | ✓    | ✓     |
| [ITA](/haut.ai/haut.ai-features/algorithms/body-skin-analysis/ita.md)                                           | ✓     | ✓     | ✓    | ✓    | ✓    | ✓         | ✓   | ✓    | ✓         | ✓         | ✓    | ✓     |
| [Monk Skin Tone](/haut.ai/haut.ai-features/algorithms/body-skin-analysis/monk-skin-tone.md)                     | ✓     | ✓     | ✓    | ✓    | ✓    | ✓         | ✓   | ✓    | ✓         | ✓         | ✓    | ✓     |

Notes:

* **Sagging is neck-only** by design — it has no fallback to any other region, so it comes back `null` whenever no neck pixels are detected.
* **Chest and Back mirror Torso** for every metric, rather than being scored independently.
* **Monk Skin Tone** includes `face` — otherwise its region set matches ITA/Lines/Pigmentation/Redness/Uniformness exactly.
* **Barrier Impairment, Microscaling, Macroscaling, and Thickening** share one region set (limbs, feet, macro) and are all sub-outputs of the same Dryness algorithm family — they're computed together from one model pass.

***

{% hint style="warning" %}
Not a Haut.AI client yet?
{% endhint %}

<a href="https://haut.ai/book-a-demo?utm_source=referral&#x26;utm_medium=saas_docs&#x26;utm_campaign=Docs_SaaS_HautAI" class="button primary" data-icon="user-vneck">Book a demo</a> <a href="https://haut.ai/product/ai-skin-analysis?utm_source=referral&#x26;utm_medium=saas_docs&#x26;utm_campaign=Docs_SaaS_HautAI" class="button secondary" data-icon="external-link">Platform overview on haut.ai</a>


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://docs.saas.haut.ai/haut.ai/haut.ai-features/algorithms/body-skin-analysis/regions-and-metrics.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.