Instantly detect your browser user agent string, browser name and version, operating system, device type, and rendering engine. Essential for web developers and compatibility testing.
A user agent (UA) string is sent by your browser to every website you visit. It identifies your browser name and version, operating system, and device type. Websites use it to serve appropriate content and layouts.
Websites use UA strings for analytics (what browsers visit), serving mobile vs desktop layouts, A/B testing, security (blocking known bad bots), and enabling browser-specific CSS or JavaScript workarounds.
Yes. Chrome DevTools allows UA spoofing in the Network conditions panel. Extensions like User-Agent Switcher also work. This lets you test how websites behave on different browsers or devices without switching devices.
Blink is the rendering engine used by Chrome, Edge, Opera, and most modern browsers. Firefox uses Gecko. Safari uses WebKit. Rendering engines determine how HTML, CSS, and JavaScript are processed and displayed.
User agents have a long history of inflating compatibility strings. The "Mozilla/5.0" prefix appears on almost every modern browser for historical reasons. This is why parsing UAs is complex.
Your IP address identifies your network connection. Your user agent identifies your browser software. Together they can be used for browser fingerprinting — identifying users without cookies.
Yes. Mobile apps that use WebView or make HTTP requests send user agents. They often include the app name and version in addition to the underlying browser engine.