Which ports does it know?

Well-known ports (0-1023) fully, registered ports (1024-49151) for common services, ephemeral range (49152+) documented but not individually listed.

Is the list IANA-official?

Yes — matches IANA's registered services. Some ports have both official and common-convention uses; both are shown.

Separate namespaces — port 53 TCP and port 53 UDP are different things. DNS uses both. The tool shows protocol per service.

Registered with IANA in 1995. Changing SSH's port is possible (security through obscurity) but most tools default to 22.

Look up common services for any TCP/UDP port number. Part of the DevTools Surf developer suite. Browse more tools in the Networking collection.

IANA maintains the official port number registry, with well-known ports (0-1023) requiring IETF approval for assignment.
Port 80 was assigned to HTTP by Tim Berners-Lee in 1991, while port 443 was assigned to HTTPS in 1994.
There are 65,535 available TCP and UDP ports per IP address, with ports 49152-65535 designated as dynamic/ephemeral ports.

Which ports does it know?: Well-known ports (0-1023) fully, registered ports (1024-49151) for common services, ephemeral range (49152+) documented but not individually listed.
Is the list IANA-official?: Yes — matches IANA's registered services. Some ports have both official and common-convention uses; both are shown.
What's the difference between TCP and UDP ports?: Separate namespaces — port 53 TCP and port 53 UDP are different things. DNS uses both. The tool shows protocol per service.
Why is port 22 always SSH?: Registered with IANA in 1995. Changing SSH's port is possible (security through obscurity) but most tools default to 22.

Look up common services for any TCP/UDP port number. Part of the DevTools Surf developer suite. Browse more tools in the Networking collection.

IANA maintains the official port number registry, with well-known ports (0-1023) requiring IETF approval for assignment.
Port 80 was assigned to HTTP by Tim Berners-Lee in 1991, while port 443 was assigned to HTTPS in 1994.
There are 65,535 available TCP and UDP ports per IP address, with ports 49152-65535 designated as dynamic/ephemeral ports.

Which ports does it know?: Well-known ports (0-1023) fully, registered ports (1024-49151) for common services, ephemeral range (49152+) documented but not individually listed.
Is the list IANA-official?: Yes — matches IANA's registered services. Some ports have both official and common-convention uses; both are shown.
What's the difference between TCP and UDP ports?: Separate namespaces — port 53 TCP and port 53 UDP are different things. DNS uses both. The tool shows protocol per service.
Why is port 22 always SSH?: Registered with IANA in 1995. Changing SSH's port is possible (security through obscurity) but most tools default to 22.