Standard Documentation

User-Agent Strings: Testing Browser Compatibility and Performance

Updated Jan 12, 20265 min read

A User-Agent (UA) string is the digital fingerprint your browser sends to every website you visit. It tells the server your browser version, operating system, and hardware type. For developers, the User-Agent Generator is essential for testing server-side logic and responsive client-side features.

Why Test with Different User-Agents?

Many modern websites use UA sniffing to deliver optimized experiences:

  • Mobile Redirection: Ensure your site correctly identifies a mobile user and serves the responsive layout.
  • Feature Parity: Check if certain features (like WebGL or specific CSS properties) are being enabled or disabled based on the reported browser.
  • Crawler Simulation: Test how your SEO metadata appears to search engine bots (Googlebot, Bingbot).
  • Security Rules: Validate that your WAF (Web Application Firewall) correctly blocks or allows specific browser categories.

💡 Scraping & Automation

If you're building web scrapers or automated testing scripts (Playwright/Puppeteer), rotating your User-Agent is the best way to prevent being flagged as a bot. Our generator provides a fresh pool of authentic strings to keep your scripts running smoothly.

A Truly Mixed Pool

Our generator doesn't just give you one string. It provides a randomized selection of Chrome, Safari, Firefox, and Edge headers across Windows, macOS, iOS, and Android. Generate up to 50 at a time and copy them directly into your testing suite.

Stop hardcoding UA strings. Get a diverse list today with the User-Agent Generator.

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