Ettercap
tcpdump
Wireshark
SmartSniff
netcat
NetworkMiner
Packet Sender
PortMapper
HTTP Debugger
Surge for Mac
Weer
Charles Proxy
James
HTTP Headers
HTTP Toolkit
mitmproxy
HTTP Debugger is a professional HTTP sniffer and analyzer for developers.
You can use HTTP Debugger to debug HTTP API calls to a back-end and between back-ends.
HTTP Debugger is very easy of use, with clean UI, and short ramp-up time.
It's not a proxy, and does not produce network issues!
Ettercap
HTTP Debuggertcpdump - tcpdump is a common packet analyzer that runs under the command line.
Surge for Mac - Advanced Web Debugging Proxy for Mac & iOS
Wireshark - Wireshark is a network protocol analyzer for Unix and Windows. It lets you capture and interactively browse the traffic running on a computer network.
Weer - A HTTP protocol debugger with Chrome DevTools frontend interface
SmartSniff - SmartSniff is a packet sniffer that capture TCP/IP packets and display them as sequence of conversations between clients and servers.
Charles Proxy - HTTP proxy / HTTP monitor / Reverse Proxy