Here is a list of mostly used debugging performance checking and HTTP troubleshooting tools.  These software and tools can be used anywhere in any site.

• Use Charles HTTP Proxy for all my HTTP troubleshooting needs.
• Firefox Web Developer tools
• Firefox Live HTTP Headers Extension
• Use Fiddler2, which is a free, it is a highly configurable proxy; works with all browsers, allows header inspection/editing/auto modification on request/response.
• Ethereal it is used for troubleshooting, analysis, software and protocol development, and education. – It runs on all popular computing platforms, including Unix, Linux, and Windows.
• Wireshark – To view full HTTP headers and actions (get/post/).