Fiddler: Http debugging proxy

Fiddler is an HTTP debugging proxy that logs all HTTP traffic between your computer and the Internet. Fiddler is simpler in use and provides lots of information regarding the data flow.
1. It allows you setup break points on incoming and outgoing request/response.
2. Modify incoming and outgoing response/ request to test some edge cases.
3. Gives complete information about request, response headers.
4. Provides cookies information.
5. Round trip time taken by request.
6. Can simulates slow internet connect speed. It helps in testing web applications in slow internet connections.
Click here to download fiddler