Port checker
This checks a port on your own connection's public IP - useful for confirming whether a port you forwarded is reachable from outside. You can only scan your own connection.
Common:
What is a port?
A port is a numbered channel on your connection (0-65535) that lets a
device run many services at once. Web traffic uses 443
(HTTPS), email and games each have their own. An open
port accepts connections; a closed one refuses them.
Common ports
80/443- HTTP / HTTPS (websites)22- SSH (secure remote login)53- DNS3389- Remote Desktop (RDP)
Should a port be open?
Only open (forward) a port when a specific app needs it, and close it when you're done. Unnecessary open ports widen your attack surface.