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.

For more information, please see the following knowledge base articles:

KB Article Web redirection and "cloaking" with classic ASP script
KB Article HTTP Redirector Plug-In

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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