Subdomain
A subdomain is a domain name that sits below another domain in the DNS hierarchy.
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Subdomain Aliases: hostname prefix, child domain.
Definition
A subdomain is a domain name that sits below another domain in the DNS hierarchy.
How it works
Each label to the left of your domain steps one level deeper: blog.example.com and shop.example.com can run on different servers, publish their own records, even delegate to entirely different nameservers — all without registering anything new. One registration, as many named services as you care to create.
Example: blog.example.com and shop.example.com are subdomains of example.com.
Often confused: blog.example.com is a subdomain; example.com/blog is a path on the same site. DNS only sees the part before the slash.
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Last reviewed 2026-07-19.