User-Agent Generator
See your current browser user agent and build sample UA strings for any browser and platform.
Runs entirely in your browser. Nothing is uploaded or stored.
How to use this tool
Your live browser user agent appears in the first box automatically, so you can read or copy it right away with the Copy current button. To build a different string, pick a browser (Chrome, Firefox, Safari or Edge) and a platform (Windows, macOS, Android or iOS), then press Generate UA string. The result is a realistic sample user agent you can copy and paste into a request header, an HTTP client, or a test fixture. This is a user agent switcher for building and copying strings only; it does not change how your real browser reports itself to websites.
How it works
Every modern user agent follows the same loose template. It starts with the legacy prefix "Mozilla/5.0", then a parenthesized section that describes the operating system and device, then the rendering engine (for example AppleWebKit or Gecko), and finally one or more product tokens naming the browser and its version. This tool reads your real string from navigator.userAgent and, for the generator, it fills that template with current platform and version tokens for the browser and platform you choose. Because the format is well known, the same pattern works as a fake user agent list for local testing, a browser user agent string generator for QA, or a quick way to compare test header strings across devices.
A real example
Choose Chrome on Windows and the tool produces a string similar to:
Switch the platform to Android and the parenthesized section changes to something like "(Linux; Android 14; SM-S918B)" while the Chrome and Safari tokens stay, which is exactly how Chrome reports itself on a Samsung phone. Copy whichever string you need and drop it into your test.
Common questions
Does this change my real user agent?
No. The tool only generates text that you can copy. To actually send a different user agent you must set it in your HTTP client, a browser developer tools override, or a request header in your own code.
What is a user agent string used for?
Servers read the user agent to learn which browser, version and platform sent a request. Developers use it for feature detection, analytics, and serving the right layout, which makes a browser user agent string generator handy when testing those paths.
Are the generated strings real?
They use realistic, current version tokens that match the format real browsers send, so they work well as a fake user agent list for testing. Exact version numbers change often, so adjust the version digits if you need a specific build.
Can I copy the string on mobile?
Yes. Both Copy buttons work on phones and tablets. Tap Copy current for your own device string or Copy generated for the one you built, then paste it wherever you need it.
Is using a custom user agent allowed?
Setting a user agent for your own testing is normal. Spoofing one to bypass access rules or terms of service is not. These strings are provided for development and testing only, not professional or legal advice.