User Agent Analyzer

Deep analysis of user agent string components and their meanings.

📖 Complete String

Analyzing User Agent Components

User agent analysis involves breaking down the UA string into its component parts to understand browser capabilities, system information, and device characteristics. Each token in the string serves a specific purpose for server-side detection and content adaptation.

Deep UA analysis helps developers understand the messy history of browser detection and why modern user agents contain so many seemingly redundant tokens. This knowledge is essential for accurate browser feature detection.

Mozilla Compatibility Token

Nearly every browser includes "Mozilla/5.0" at the start. This dates back to when servers would only send advanced content to Netscape Navigator (codenamed Mozilla). Other browsers adopted this token to receive full content.

Platform Information Block

The parenthetical section contains operating system, CPU architecture, and sometimes device information. This is the most reliable section for system detection but formats vary significantly between browsers and platforms.

Rendering Engine Tokens

AppleWebKit, Gecko, and Blink identifiers indicate the rendering engine. Chrome-based browsers use Blink (fork of WebKit), Firefox uses Gecko, and Safari uses WebKit. Engine version often differs from browser version.

Browser Identification

The actual browser name and version appear near the end. Edge includes Chrome's token for compatibility, and Chrome includes Safari's. Always check for more specific tokens before generic ones during parsing.