Wireshark : Wireshark is the world's foremost network protocol analyzer. It lets you see what's happening on your network at a microscopic level. It is the de fac...
httpbin.org : A simple HTTP Request & Response Service.
GoReplay : GoReplay is an open-source tool for capturing and replaying live HTTP traffic into a test environment in order to continuously test your system with r...
Pact : Fast, easy and reliable testing for integrating web apps, APIs and microservices. Pact is a code-first tool for testing HTTP and message integrations ...
An HTTP Viewer and HTTP Sniffer for IE and Firefox