---
title: http.user_agent
description: The HTTP `User-Agent` request header, which contains a characteristic string to identify the client operating system and web browser.
image: https://developers.cloudflare.com/core-services-preview.png
---

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#  http.user\_agent 

`http.user_agent` ` String ` 

The HTTP `User-Agent` request header, which contains a characteristic string to identify the client operating system and web browser.

Example value:

```
"Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36"
```

Categories: 
* Request
* Headers

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```