Server Fault is a question and answer site for system and network administrators. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I realise that it would be a bit 'volatile', but I can't find a list of port numbers and the applications or services that would use them by default.

Sometimes seeing javaw.exe just isn't good enough :)

Note: To see the ports in use on a Windows OS machine, use netstat at the command line or download TCPview for example.


Additional question. Can an application use a range of ports?

share|improve this question
up vote 1 down vote accepted

If you want the list of officially registered ports you can look on IANA.

Can an application use a range of ports?

Absolutely. For example SIP, or H.323 typically have half a dozen different connections open at the same time for all the content streams and control streams. FTP uses at least two and occasionally more ports.

share|improve this answer
This is as good as it gets - Thank you! – ian_scho Jun 26 '10 at 14:14

On a non-windows system,

cat /etc/services

Will show the IANA registered names for ports. Of course, this doesn't really tell you which applications will use which ports, but it at least gives you a hint about what ports mught be used. For example, your email application will likely use one or more of the following: smtp, pop3, imap, pop3s, imaps.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.