A top-level domain (TLD) is one of the domains at the highest level in the hierarchical Domain Name System of the Internet after the root domain. The ".com" ".org" ".me" you see at the end of links are all considered top-level domains.
For example, in the domain name www.example.com., the top-level domain is .com.
Not all characters are able to be used as a top level domain. There is a list of all TLDs in existence here. Additionally, not all TLDs are offered through Bitly's Complementary Domain program so if there's one you'd like that isn't offered you are recommended to purchase it directly from a domain provider.
Keep these things in mind as you choose and set up a custom domain:
- The domain for your short links must be different than your website domain.
- It can't be more than 32 characters long, including the dot.
- If you haven't added one yet, Bitly offers a complimentary domain. However, if you add your own domain, you won't be able to redeem this offer later.