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User-Agent Switcher & Header Simulator

Copy search engine crawler bot strings, check mobile response structures, and verify user agent headers.

Test Crawl and Device Compatibility

Some web servers serve different code to search engine spiders or mobile devices. This user-agent switcher simulator lets you copy and test target headers to audit site responsiveness.

Key Benefits & Features

Bot Header Libraries

Lists strings for Googlebot and Bingbot.

Mobile Client Switch

Includes iOS iPhone agent headers.

Responsive Testing

Verify desktop vs mobile server outputs.

How to Use the User-Agent Switcher Auditor Step-by-Step

This utility runs entirely inside your browser using client-side JavaScript. We prioritize your security: none of your inputted text is logged or stored.

  1. 1

    Select a target client header device (e.g. iPhone).

  2. 2

    Copy the header text string.

  3. 3

    Use it inside developer consoles to simulate device access.

Practical Examples

Input Example

Select: Googlebot

Expected Output
Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)

Frequently Asked Questions (FAQ)

What is a user agent header?

A text string sent by browsers to web servers identifying the browser, version, and device OS.

Explore category: Traffic & SEO

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