Internet top-level domains

This list of Internet top-level domain extensions contains top-level domains, which are those domains in the DNS root zone of the Domain Name System of the Internet. The official list of all top-level domains is maintained by the Internet Assigned Numbers Authority (IANA) at Root Zone Database.^[1] IANA also oversees the approval process for new proposed top-level domains. As of October 2016, the root domain contains 1503 top-level domains,^[2] while a few have been retired and are no longer functional.

https://en.wikipedia.org/wiki/List_of_Internet_top-level_domains 

http://www.iana.org/domains/root/db