A simple TCP/UDP client designed for quick debugging. Supports connecting to remote systems as well as listening.
All of this is in the browser, so no need for external websites to do the connections for you. Works offline/local/etc...
Inspired by the venerable netcat project by Hobbit.
Note that Chrome or your OS or your router might restrict what addresses, ports, or protocols are allowed when listening for new connections.
TCP listening has been tested on CrOS and works. UDP listening appears to be not well supported by Chrome itself.
This can be installed from the Chrome Web Store: https://chrome.google.com/webstore/detail/nllngonbmjjafbaalbkmopdbbeonoojo