IP Address With a Port: IPv4 and IPv6 Examples

A port identifies a service endpoint on a host. Put :port after IPv4; bracket an IPv6 address before adding a port in a URL.

Examples at a glance

https://[2001:db8::1]:8443/

IPv4 endpoint

Complete URL: http://192.0.2.10:8080/
HTTP service on port 8080.
Address: 192.0.2.10
The bare IPv4 address.
Port: 8080
The service number.

IPv6 endpoint

Complete URL: https://[2001:db8::1]:8443/
HTTPS service on port 8443.
Address: 2001:db8::1
Brackets surround this address in the URL.
Port: 8443
The colon after ] introduces the port.

Why IPv6 needs brackets

IPv6 already contains colons. In https://[2001:db8::1]:8443/, brackets delimit the host and 8443 is the port. The bare address remains 2001:db8::1.

Ports are separate from addresses

TCP and UDP port numbers are 16-bit values. Applications generally use service ports from 1 to 65535; port 0 has special uses. A syntactically valid URL does not prove a service is listening.

Choose the matching tool

Use the URL analyzer for a complete HTTP/HTTPS endpoint. The IP validator accepts only bare addresses, so remove scheme, brackets and port first.