> 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-metrics-2-0/hydration-algorithm-experimental.md).

# Hydration Algorithm (experimental)

What the experimental Hydration Algorithm estimates, the metrics it returns, and why hydration readings shift through the day.

## About Algorithm

{% hint style="warning" %}
**Disclaimer**

The Hydration Algorithm is experimental. Results are approximate, may vary under different conditions, and are not intended for medical diagnosis or treatment.<br>

Hydration is a dynamic skin parameter that can change quickly throughout the day due to the skin’s natural properties. Actual skin hydration depends on multiple factors—such as internal body hydration and environmental temperature—that cannot be accurately assessed from a single photo.<br>

Results may also differ between images not because hydration changes within minutes, but due to how the skin reflects light under different lighting conditions (e.g., warm lamp vs. daylight).
{% endhint %}

1. This Algorithm estimates the visual signs of dehydrated skin on the face.
2. The Main Metric for this Algorithm is the Hydration Score, with a range from 0 to 100.
   1. Values from 70 to 100 are considered as a relatively good skin condition.
   2. Values below 70 are considered as visible signs of dehydration.
3. There are several Submetrics for this Algorithm:
   * Hydration Level - a human-readable class label representation of Hydration Score.

***

## Algorithm API

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

See [Hydration Result Scheme](/haut.ai/developers/saas-api-overview/api-for-face-metrics-2.0/hydration.md).

***

{% hint style="warning" %}
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{% endhint %}

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