User-Agent String Lookup

User-Agent String Lookup: Core Features & How It Works

When you need to test web page compatibility across different browsers or spoof your client identity for a web scraper, manually searching for the correct User-Agent string is time-consuming. This tool provides a structured list of common User-Agent strings covering both desktop and mobile devices. You can browse and copy them with one click to set HTTP request headers or use them in browser developer tools. A User-Agent is a request header field in the HTTP protocol used to identify the type, version, operating system, and rendering engine of the client software (such as a browser) initiating the request.

Why Use Our User-Agent String Tool?

• Organized Categories for Major Environments: The list is categorized by desktop and mobile devices, including classic User-Agents for mainstream browsers like Chrome, Firefox, Safari, and Edge on Windows, macOS, iOS, and Android systems.
• One-Click Copy for Instant Use: Click the input box next to your target entry, and the complete User-Agent string will automatically copy to your clipboard. No manual text selection is required, greatly improving your workflow.
• Standard Formats, Ready to Deploy: The provided strings are all in standard HTTP request header formats (e.g., "Mozilla/5.0..."), which can be used directly in your code, Postman, or browser emulators without any secondary processing.

How to Use This Tool

1. Open the tool page, where you will see two main categories: "Desktop" and "Mobile".
2. Based on your testing or simulation needs, find the target browser or device entry under the corresponding category (e.g., "Chrome on Windows 10" or "Safari on iPhone").
3. Click the text area on the right side of the entry. The page will display a "Copied" prompt.
4. Paste and use the string in your code editor, command-line terminal, or the network request header settings of your browser's developer tools.

Frequently Asked Questions (FAQs)

Q: How do I get the User-Agent for the latest version of Chrome?
A: This tool mainly includes verified, commonly used classic version strings. To get the exact User-Agent for the latest browser version, the most reliable method is to enter the navigator.userAgent command directly into the developer tools console of that installed browser.

Q: Can the copied string be used directly in the Python requests library?
A: Yes. The copied string can be used directly as the value for the 'User-Agent' key in your headers dictionary. For example: headers = {'User-Agent': 'your copied string'}.

Important Notes

Please note that User-Agent strings change with browser version updates, and this tool's list cannot guarantee the inclusion of all the absolute latest versions. Some websites will detect and block overly outdated or obviously forged User-Agents. When using them for web scraping, please rotate them reasonably and comply with the target website's robots.txt protocol and relevant laws and regulations. If copying fails after clicking, please check if your browser has disabled clipboard access permissions, or try manually selecting the text to copy.

Technical Notes & Best Practices

For web developers and QA testers, using this tool to quickly switch User-Agents to simulate different clients is an efficient way to debug CSS or JavaScript browser compatibility issues. You can override the User-Agent in the "Network Conditions" or "Device Mode" of your browser's developer tools. For web scraper development, a common practice is to build a User-Agent pool. Selecting multiple strings for different browsers and systems from this tool, adding them to a list, and randomly choosing them can effectively reduce the risk of being identified and blocked by bot detection mechanisms due to frequent requests from a single User-Agent. For example, when simulating mobile access, you can alternate between strings like "Mozilla/5.0 (iPhone; CPU iPhone OS 14_0 like Mac OS X) AppleWebKit/605.1.15..." and "Mozilla/5.0 (Linux; Android 10; SM-G973F) AppleWebKit/537.36...".