> For the complete documentation index, see [llms.txt](https://docs.caf.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.caf.io/caf-api/connect/available-resources/face-authentication.md).

# Face Authentication

Face Authentication is a biometric service that enables face registration and authentication through facial comparison. This resource provides endpoints to register faces for individuals and query facial authentication attempts.

{% hint style="info" %}
**Authentication Requirements:**

* Regular endpoints use `OAuth2` authentication with base URL: `https://api.us.prd.caf.io`
* For enhanced security, some endpoints may also support `mTLS` authentication with base URL: `https://mtls.us.prd.caf.io`
* For information on implementing `mTLS`, access [Using mTLS](/caf-api/connect/authentication/using-mtls.md)
  {% endhint %}

## Face Registration

The registration endpoint allows associating a facial image with a person identifier (`personId`), creating a biometric reference that will be used later for authentication.

{% hint style="info" %}
Faces registered by this endpoint will be used for facial comparison through the CafSdk or [CafFaceLiveness](https://docs.caf.io/caf-sdk/web-javascript/getting-started/face-liveness-and-face-authenticator) SDKs. SDKs documented as deprecated will not necessarily use these facial registrations.
{% endhint %}

{% openapi src="/files/YBSP4axRb2aZqvBayAF1" path="/" method="post" %}
[register-faces.yaml](https://3218940882-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FbVxCOSyBojfSIE5fcpfH%2Fuploads%2Fgit-blob-f97dab14a41c49d2d83a527f5d558b5ff7ff391f%2Fregister-faces.yaml?alt=media)
{% endopenapi %}

## Face Authentication Attempt Query

The query endpoint allows retrieving information about a specific facial authentication attempt, including URLs of the images used.

{% openapi src="/files/nrwCTp6p14sil6WlyNgm" path="/attempts/{attemptId}" method="get" %}
[get-attempt.yaml](https://3218940882-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FbVxCOSyBojfSIE5fcpfH%2Fuploads%2Fgit-blob-78865ee29598fed74645fa182fa6c52d7335417d%2Fget-attempt.yaml?alt=media)
{% endopenapi %}


---

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