User Agent Parser: Analyze Browser & OS Details
Inspect and parse user-agent strings to extract browser versions, operating systems, and device categories locally in your browser. All analysis runs client-side with no server logs.
Parsed Engine Results
What Is a User Agent String?
A **User Agent (UA) String** is a header text line sent by your web browser to web servers with every request. It acts as a declaration of your browser software name, layout engine, operating system, and system version details. Web applications use this header to customize layouts, serve compatible scripts, or analyze traffic patterns.
This tool processes your data locally in your browser, so no inputs need to be sent to our server. All string parsing is executed instantly in client-side JavaScript, leaving no record of your device signature on external databases.
Key Features
- Local Environment Detection: Load and parse your active browser's user-agent string in a single click.
- Core Properties Split: Automatically extracts Browser Type, Operating System, Engine, and Device category.
- Zero Data Retention: Runs fully in your local session RAM. Closing the tab wipes all parsed values instantly.
- Completely Offline: Works without sending queries to external API endpoints.
How To Use
- 1 Load String: Click "Load My Current User-Agent" to load your browser signature.
- 2 Custom Input: Alternatively, paste any target UA string from your server logs.
- 3 Inspect Parsing: The tool parses and updates results dynamically as you type.
- 4 Use Output: Read browser name, engine layout, and OS metrics for debugging.
Understanding the Structure of User Agents
Modern User Agent strings are notoriously complex and contain legacy compatibility strings (like Mozilla/5.0 and like Gecko) to prevent older web servers from blocking modern browsers. This parser performs substring inspections to separate values:
- Browsers Supported: Recognizes Firefox, Chrome, Safari, and Edge.
- OS Environments: Recognizes Windows, macOS, Android, and iOS.
- Device Categories: Identifies mobile handsets, tablet displays, or desktop computers.
Technical Limitations: This utility utilizes basic substring matching logic for major client configurations. It is not designed to parse web crawlers (such as Googlebot or Bingbot), minor niche browsers, or command-line clients. Furthermore, modern browsers are increasingly reducing or freezing user-agent signatures (User-Agent Reduction) to enhance privacy, meaning some details may default to broad classifications.
Almost all modern browsers prefix their User Agent with "Mozilla/5.0" and include "AppleWebKit/537.36 (KHTML, like Gecko) Chrome/... Safari/..." for backward compatibility. This ensures servers render standards-compliant HTML rather than blocking newer engines.
No. This tool processes your data locally in your browser, so no inputs need to be sent to our server. All parsing runs client-side in your local browser sandbox.
User-Agent Client Hints is a newer web API standard designed to replace traditional User-Agent strings. It allows browsers to selectively share hardware or version details only when requested by the server, protecting user privacy.
Privacy Promise
This tool runs entirely inside your browser. Your files never leave your device.