Next are third-level domains, which are written immediately to the left of a second-level domain. There can be fourth- and fifth-level domains, and so on, with virtually no limitation. An example of an operational domain name with four levels of domain labels is Each label is separated by a full stop (dot). 'sos' is said to be a sub-domain of '', and 'state' a sub-domain of '', etc. In general, subdomains are domains subordinate to their parent domain. An example of very deep levels of subdomain ordering are the IPv6 reverse resolution DNS zones, e.g.,, which is the reverse DNS resolution domain name for the IP address of a loopback interface, or the localhost name.
A domain name is an identification string that defines a realm of administrative autonomy, authority or control within the Internet. Domain names are formed by the rules and procedures of the Domain Name System (DNS). Any name registered in the DNS is a domain name. Domain names are used in various networking contexts and for application-specific naming and addressing purposes. In general, a domain name represents an Internet Protocol (IP) resource, such as a personal computer used to access the Internet, a server computer hosting a web site, or the web site itself or any other service communicated via the Internet. In 2017, 330.6 million domain names had been registered.[1]
Domains that are indexed on Google and highly ranked are particularly attractive to traders. Other SEO aspects, such as backlink profiles or the search volume of the keywords in domain names, also play a significant role in appraising value. Design can also positively affect the price of a domain. Short and succinct names that are easy to remember are especially advantageous. Endings are further factors that should be taken into account. Top-level domains (TLDs) such as .com or .org are by far the most sought-after endings.
Not every registrar sells every top-level domain, so if you want an uncommon TLD like .pizza, you might have to try a few registrars. Unusual TLDs often cost more than a standard .com address, but provide built-in memorability and give you more name options, since far fewer .pizza addresses are already taken. You can check name availability at any registrar that offers the TLD you want.

Now it’s time to see if your domain name choices are available. Once you’ve come up with a few strong domain candidates, it’s time to plug them into Namecheap’s domain name search bar. We will search available domain names for you and let you know if your first choice of second-level domain or TLD is available. We’ll also suggest some alternate TLDs you might try if your first domain choice isn’t available.