SudoSecurity

Open port checker

See which ports on your own connection are reachable from the internet, like SSH, RDP or databases.

Your public IP: 216.73.216.233. We can only test the address you're connecting from, so this can't be used to scan anyone else.

Leave empty to test common ones: 22, 80, 443, 3306, 3389, 5432, 6379, 25565.

How it works

Our server tries a normal TCP connection to each port on your public IP and waits up to 3 seconds. Nothing is sent after connecting and results aren't stored. Behind home routers, a port is only open if you've set up port forwarding.

Close a port on Linux

sudo ufw default deny incoming
sudo ufw allow 22/tcp     # keep SSH, or limit it to your IP
sudo ufw enable
sudo ss -tlnp             # see what is listening

Databases (MySQL, PostgreSQL, Redis, MongoDB) and RDP should almost never be public. Bind them to 127.0.0.1 or reach them over a VPN or SSH tunnel. Hardline's firewall controls set this up with a safe default-deny policy.

Known port names

21 FTP, 22 SSH, 23 Telnet, 25 SMTP, 53 DNS, 80 HTTP, 110 POP3, 143 IMAP, 443 HTTPS, 445 SMB, 587 SMTP submission, 993 IMAPS, 1433 MS SQL, 2375 Docker API, 3306 MySQL, 3389 RDP, 5432 PostgreSQL, 5900 VNC, 6379 Redis, 8080 HTTP (alt), 8443 HTTPS (alt), 9200 Elasticsearch, 11211 Memcached, 25565 Minecraft, 27017 MongoDB