Subdomain Finder

Subdomain Finder is straightforward to use. To start, enter the target domain address and click Scan. The tool will take you to the Subdomains section of SE Ranking’s Competitive Research, which reveals comprehensive, up-to-date data on every found subdomain—access data on traffic volume, share, and cost, along with the number of keywords. Filter subdomains by any metrics and access the detailed keywords report by clicking on the number of keywords. Finally, click the Export button to download the report in the .csv or .xsl format.

Our subdomain scanner is designed for maximum accuracy. It combines data from search engines with supplementary databases and also sends requests directly to domain service providers. This approach ensures that the results are as complete and up to date as possible. The tool is also secure—none of the domains or subdomains you check are stored or made public.

There are multiple ways to discover subdomains:

• Manually: by entering the site:* operator in Google search.
• Via DNS records: by using the nslookup command.
• With online tools: such as our subdomain scanner, which automates the process and typically provides more comprehensive results.

Yes. A subdomain takeover occurs when a subdomain is pointing to an inactive external service, yet the related CNAME record remains in the DNS records. In this case, attackers can set up their own hosting for that subdomain and gain unauthorized control over it. Regularly checking your DNS configurations helps prevent this type of vulnerability.

You can check DNS records by running the nslookup command in the command line. It retrieves all available DNS records for a given domain, including subdomains. This command works on Windows, Linux, and macOS systems. For more detailed results, specialized DNS lookup tools or online scanners can also be used.

SEO-wise, subdomains are separate sites. They are associated with the domain name but not with the site itself. Subdomains are used for different tasks:

• site localization for various regions

• separating categories of goods, services, or information

• publication of user-generated content

• separate render of the site application

• testing new site elements

The subdomain is displayed as a separate search result. Most search engines, including Google, consider subdomains as separate sites—they crawl, index, and rank them independently from the main site. Therefore, optimising the main domain and its subdomains is equally essential.

Technically, yes. The www prefix is a subdomain, though in practice it usually redirects to the main domain. Historically, www was used to identify sites that relied on the World Wide Web protocol. Today, many hosting providers automatically create the www subdomain for new domains and configure it to redirect to the root domain.

Yes, subdomains can be hidden from search engines and indexing, although they still exist and are accessible if someone knows the exact URL. Methods include:

• Blocking crawlers with a robots.txt disallow directive.
• Using noindex or none directives in the page’s meta tags to hide subdomains from indexing.
• Setting X-Robots-Tag HTTP headers to noindex or none on the subdomain server.

In theory, there is no strict limit to the number of subdomains a domain can host. However, some DNS service providers impose practical restrictions. For example, GoDaddy allows up to 500 subdomains per domain. For enterprise setups, dedicated DNS services may support thousands of subdomains without issue.