Free User Agent & Browser Info Checker

Understanding User Agent Strings and Browser Information

The User Agent string is a piece of text that your browser sends to websites to identify itself. It contains information about your browser, operating system, and device. This information helps websites deliver content optimized for your specific setup.

What is a User Agent String?

A User Agent string typically contains the following information:

• Browser Name and Version: Identifies which web browser you're using and its version number.
• Rendering Engine: The core software component that interprets HTML, CSS, and JavaScript (e.g., Gecko, WebKit, Blink).
• Operating System: Your device's operating system and version.
• Device Information: For mobile devices, this may include the device model.
• Compatibility Flags: Additional information about browser compatibility.

Example User Agent Strings

Browser	Example User Agent String
Chrome (Windows)	Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.124 Safari/537.36
Firefox (macOS)	Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:89.0) Gecko/20100101 Firefox/89.0
Safari (iOS)	Mozilla/5.0 (iPhone; CPU iPhone OS 14_6 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/14.0 Mobile/15E148 Safari/604.1
Edge (Windows)	Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.124 Safari/537.36 Edg/91.0.864.59

Why User Agent Information Matters

Understanding your browser and device information is important for several reasons:

• Compatibility: Websites can deliver content optimized for your specific browser and device.
• Troubleshooting: When reporting issues to websites or developers, your user agent information helps them understand your environment.
• Security: Being aware of your browser's capabilities helps you understand potential security implications.
• Privacy: Your user agent can contribute to your browser fingerprint, which can be used to track you across websites.

Browser Fingerprinting

Browser fingerprinting is a technique used to identify and track users based on their browser and device characteristics. Unlike cookies, fingerprinting doesn't require storing anything on your device. Instead, it uses information like your user agent, screen resolution, installed plugins, and supported features to create a unique profile.

To protect your privacy, consider:

• Using privacy-focused browsers like Firefox or Brave
• Installing anti-fingerprinting extensions
• Using a VPN to mask your IP address
• Regularly clearing cookies and browsing data

User Agent Evolution

User agent strings have evolved over time, often carrying legacy information for compatibility reasons. For example, most modern browsers include "Mozilla" in their user agent string, which dates back to the early browser wars. Similarly, Chrome-based browsers include "Safari" in their user agent because they use WebKit-derived rendering engines.

In recent years, there has been a push to simplify user agent strings to reduce their use for fingerprinting while still providing necessary information for website compatibility. This is part of a broader initiative called "User Agent Client Hints" which provides a more structured way for browsers to share their capabilities with websites.