Can I specify a TCP/IP port number for my web-server in DNS? (Other than the standard port 80)

Unfortunately the standard DNS A-record (domain name to IP address) used by web-browsers to locate web-servers does not include a port number.
Web-browsers use the URL protocol prefix (http://) to determine the port number (http = 80, https = 443, ftp = 21, etc.) unless the port number is specifically typed in the URL (for example "" = port 5000).

If you need to run a web-server on a TCP/IP port other than 80, the visitor will need to specify this port directly in the URL (see above), or you need to point the DNS A-record to the IP address of a different web-server (running on port 80) which redirects your domain name to your own server IP address and port number.
For details, please see the reference articles below.

Related KB articles:

3 Dec 2015 14:49 UTC
Timur Ahmetshin
Isn't SRV records are made for port number resolution?
JH Software
5 Jan 2016 19:37 UTC
JH Software
@Timur Ahmetshin
Yes they are. But unfortunately Internet browser programs don't use them.
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