HttpWatch - HttpWatch: The ultimate HTTP Sniffer for Chrome, IE and iOS
Charles Proxy - HTTP proxy / HTTP monitor / Reverse Proxy
Postman - The Collaboration Platform for API Development
HTTP Toolkit - Beautiful, cross-platform & open-source tools to debug, test & build with HTTP(S). One-click setup for browsers, servers, Android, CLI tools, scripts and more.
Insomnia REST - The most intuitive cross-platform REST API Client ð´
Weer - A HTTP protocol debugger with Chrome DevTools frontend interface