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Subdomain

Portrait of Robert Klimant, co-founder of Roelu Studio
Robert KlimantCo-founder

What is Subdomain?

A subdomain is a section of a larger domain, created by adding a prefix before the root — for example, blog.roelu.com or docs.stripe.com. Technically, each subdomain is a distinct DNS entry that can point to its own server, application, or platform. Subdomains are commonly used to separate marketing sites from product apps, host help centers, or serve regional versions of a site.

Why it matters

Subdomains are useful when two parts of your business genuinely need to be separate — a marketing site on roelu.com and a product app on app.roelu.com. They are misused when teams put their blog on blog.company.com and wonder why it never ranks. Google treats subdomains as related but distinct properties. SEO authority does not always transfer cleanly. For content meant to support the main brand — blogs, glossaries, case studies — keep it on a subdirectory like /blog. Reserve subdomains for genuinely separate applications, like product, status, or docs.

How it works

You create a subdomain by adding a DNS record — usually a CNAME or A record — that points the prefix to a server or service. Your registrar or DNS provider exposes a dashboard where you type the subdomain name and the destination, save, and wait for the change to propagate. Unlimited subdomains are typically free once you own the root domain. From there, the subdomain behaves like an independent site: its own SSL certificate, its own hosting, its own analytics. You can host docs.company.com on a different platform than the main site without changing the root domain at all.

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