What a User-Agent string is
Every time your browser asks a website for a page, it sends a short line of text called the User-Agent. It describes the browser and the system it is running on, in a format that looks cluttered because of decades of history. A typical string mentions a browser name, a version number, a rendering engine, and an operating system, often with references to other browsers for old compatibility reasons.
Websites and servers have traditionally used that line to decide what to send back. A site might serve a mobile layout, adjust for a particular browser's quirks, or record visitor statistics grouped by browser and system.
This tool reads the string your browser exposes to scripts on the page and prints it exactly as it is, in a monospace box. It also shows three related values: Platform, Language, and whether cookies are enabled.
When you need to see it
Developers copy a User-Agent string when reproducing a bug that only occurs in one browser, when writing a rule that depends on the browser, or when filing a report that asks which browser and version they were using. Support teams often request it so they know exactly what a customer is running.
It is also useful for testing. If you change your browser's reported identity with developer tools or an extension, this page confirms what the change actually produced. And if you are curious what information your browser gives every site by default, reading the raw string is an easy way to find out.
The string is not a reliable truth. Browsers can be configured to report something different, and some newer browsers reduce the detail they include, so treat it as what the browser says about itself rather than a verified fact.
How to view and use your User-Agent
- Open the tool. The string appears automatically in the box under "Your User-Agent string".
- Read the extra tiles below it: Platform, Language, and Cookies enabled (true or false).
- Select the text in the box and copy it with your normal copy shortcut.
- Paste it into your bug report, support ticket, or test configuration.
There is no button to press and no file to upload. Nothing is sent to any outside service, because the page only reads values already available in your browser.
Caveats when reading the output
Do not try to parse the string by eye for a precise operating system version. Many browsers freeze or generalize parts of it, so a version number may not be the real one. The Platform tile comes from a browser property that is also considered legacy, and it may show a generic value that does not match your actual device.
Language reflects the browser's preferred language setting, not necessarily the language of your system or content. Cookies enabled only tells you whether the browser allows cookies at all, not whether a given site has permission to set them.
The string does not include your IP address or location. If you want to see the address websites see for your connection, use IP Address Lookup. For display details such as pixel ratio and window size, there is the Screen Resolution Checker.