A user agent is the string which describes platform, operating system and browser. User Agent is sent by the browser with other HTTP Headers to let the web server know its identity. All web browers provide a built-in User Agent string, but they can be also modified by a user.

What is my User Agent?

User Agent Lookup

Do you have a User Agent string that you want to lookup? The tool below will parse the User String, and provide you with the platform, operating system, and browser.

Enter a user-agent string:

A user agent is a piece of software that acts on behalf of a user, typically a web browser, and identifies itself to web servers when making requests for resources such as web pages or images. The user agent provides information about the software, device, and operating system being used to access the web page, which can be used by the server to deliver content tailored to the specific device or browser.

The user agent string, which contains information about the user agent, is sent as a part of the HTTP request header when a web page is requested. This information includes details such as the type and version of the web browser, the operating system and version, and device details such as screen size and resolution.

User agents can also be used to track and analyze user behavior and preferences, as well as to detect and block malicious traffic or bots.

However, the user agent string can be spoofed or modified, which can make it unreliable as a source of information about the user or device. Some browsers also have options to mask or change the user agent string, which can help protect privacy or avoid being tracked by websites.