---
title: cf.tls_client_auth.cert_fingerprint_sha256 · Cloudflare Ruleset Engine docs
description: The SHA-256 fingerprint of the certificate in the request.
source_url:
  html: https://zt-dark-mode-changelog.preview.developers.cloudflare.com/ruleset-engine/rules-language/fields/reference/cf.tls_client_auth.cert_fingerprint_sha256/index.md
  md: https://zt-dark-mode-changelog.preview.developers.cloudflare.com/ruleset-engine/rules-language/fields/reference/cf.tls_client_auth.cert_fingerprint_sha256/
---

# cf.tls\_client\_auth.cert\_fingerprint\_sha256

`cf.tls_client_auth.cert_fingerprint_sha256` String

The SHA-256 fingerprint of the certificate in the request.

This field is only filled in if the request includes a client certificate for [mTLS authentication](https://developers.cloudflare.com/ssl/client-certificates/enable-mtls/).

Example value:

```txt
"af363dc85bc942a892d3cee9796190fdb36d89cd588a4f1cb17c74a943439714"
```

Categories:

* Request
* mTLS
