Help Center/ Domain Name Service/ FAQs/ DNS Overview/ How Many Domain Name Levels Does DNS Support?
Updated on 2025-08-15 GMT+08:00
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How Many Domain Name Levels Does DNS Support?

When you create a public zone, a maximum of 16 levels of domain names (including top-level domains) are supported.

Take example as an example.

  • DNS supports the following levels for domain names with the .com suffix:
    • Primary domain name: example.com, which is considered as a level-2 domain name (including the top-level domain).
    • Subdomain: A maximum of 14 prefixes can be added before the primary domain name, for example, 1.example.com, 1.2.example.com, 1.2.3.example.com,...,1.2.3.4.5.6.7.8.9.10.11.12.13.14.example.com.
  • DNS supports the following levels for domain names with the .com.cn suffix:
    • Primary domain name: example.com.cn, which is considered as a level-2 domain name (including the top-level domain).
    • Subdomain: A maximum of 14 prefixes can be added before the primary domain name, for example, 1.example.com.cn, 1.2.example.com.cn, 1.2.3.example.com.cn,...,1.2.3.4.5.6.7.8.9.10.11.12.13.14.example.com.cn.

Domain Name Hierarchy

The domain name resolution involves a hierarchical structure and often uses recursive queries.

The following uses example.com as an example to describe the structure and levels of a domain.

  • Root domain

    A period (.) is the designation for the root domain.

    A fully qualified domain name (FQDN) ends with a period (example.com.). When you enter a domain name (example.com) in the browser, the DNS system will automatically add a period in the end.

    Root domain names are resolved by root name servers that hold the addresses of top-level domain servers.

  • Top-level domain

    Below the root domain are top-level domains, which are categorized into two types:

    • Generic top-level domain (gTLD), such as .com, .net, .org, and .top
    • Country code top-level domain (ccTLD), such as .cn, .uk, and .de

    Top-level domains are resolved by top-level domain servers that hold the addresses of second-level DNS servers. For example, the top-level domain server of .com saves the addresses of all DNS servers of second-level domains that end with .com.

  • Second-level domain

    Second-level domains (such as example.com) are subdomains of top-level domains and are resolved by second-level DNS servers, which provide authoritative domain name resolution services.

    For example, if you purchase example.com from a domain name registrar and set a DNS server for the domain name, the DNS server will provide authoritative resolution for example.com, and its address will be recorded by all top-level domain servers.

    If you host domain names on the Huawei Cloud DNS service, authoritative DNS servers will provide authoritative resolution services for your domain names.

  • Subdomain

    Second-level domains can be further divided into subdomains (such as www.example.com) to indicate specific servers or services.

Parent Topic: DNS Overview