Subdomain Finder

Discover all subdomains associated with any domain. Find hidden subdomains, competitor sub-sites, and ensure your own subdomains are configured correctly.

What you need to know

Why subdomains matter for SEO — Google treats subdomains as separate sites by default. Links and authority built on blog.example.com don't automatically benefit example.com.

Subdomains vs. subdirectories — For SEO, subdirectories (example.com/blog) are almost always better than subdomains (blog.example.com). Subdirectories inherit domain authority; subdomains start fresh.

Find forgotten subdomains — Old staging environments, forgotten microsites, and test subdomains often expose security vulnerabilities or duplicate content. Find and clean them up.

Competitor subdomain intelligence — Competitor subdomains reveal their site structure, separate product lines, international versions, and development priorities before they're publicly announced.

Frequently asked questions

What is a subdomain?

A subdomain is a prefix added to a domain name (e.g., blog.example.com, shop.example.com). Each subdomain is a separate section of the website.

Are subdomains bad for SEO?

Not inherently, but subdirectories are generally better for SEO because they consolidate authority. Subdomains work fine for genuinely separate products or services.

How do I find all my own subdomains?

Use this tool, check your DNS records in your domain registrar, or check your Google Search Console for coverage across different subdomains.

What should I do with subdomains I don't use?

Remove or redirect them. Unused subdomains waste crawl budget, can create duplicate content issues, and may expose security vulnerabilities.

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