Subdomain Finder (2025)

FAQs

How can I find subdomains? ›

DNSDumpster.com is a FREE domain research tool that can discover hosts related to a domain. Finding visible hosts from the attackers perspective is an important part of the security assessment process.

For example, Nmap can be used to identify active subdomains and then used in combination with other tools, such as vulnerability scanners, to assess the security of the website. Nmap uses various techniques, such as port scanning, to identify active subdomains, ensuring that the results are accurate and up-to-date.

The Subdomain Scanner uses the target domain's DNS server (or any other DNS server specified) to scan the DNS records for possible subdomains. While scanning, the Subdomain Scanner will also automatically identify if the domain being scanned uses wildcards (*. example.com).

Benefits of Subdomains

Distinct Presence in SERPs: Search engines treat subdomains as separate websites, distinct from the main domain. This can allow your subdomains to appear alongside your main domain in search engine results pages (SERPs), potentially enhancing your visibility and authority.

Google discovers and prioritizes the indexation of URLs based on the links pointing to those URLs. These links can be from external domains or from other accessible subdomains on the same root domain.

The term domain grabbing describes the registration or reservation of several domains for the purpose of profit maximization. These are mostly domains with generic terms, but often also protected company, brand and product names which are registered as top level domains. It can also be called cybersquatting.

The ICANN registration data lookup tool gives you the ability to look up the current registration data for domain names and Internet number resources. The tool uses the Registration Data Access Protocol (RDAP) which was created as a replacement of the WHOIS (port 43) protocol.

WHOIS is a protocol used for looking up information about domain names. It can be used to find out who owns a domain, when the domain was registered and when it expires, and other administrative contact information. It can also be used to find out which registrar a domain is registered with.

Find Subdomains of a Domain with NsLookup:

Replace “example.com” with the domain name you are interested in. This command will return a list of the authoritative name servers for the domain, which can often include the subdomains.

How do I know if something is a subdomain? ›

Subdomains are the part of a domain that comes before the main domain name and domain extension. They can help you organize your website. For example, docs.themeisle.com . In this URL, docs is the subdomain.

A subdomain, on the other hand, is another part of the URL structure that goes before the domain name. As its main purpose is for site organization, your website can work fine without it.

A Subdomain Finder is a subdomain enumeration tool that helps you discover subdomain hosts (aka subdomain FQDNs) which serve specific functions for your target (e.g. hosting public websites, private subdomains for testing web apps, URLs where you can find backups, etc.).

Subdomain hijacking, also known as dangling DNS, occurs when a threat actor gains control of a subdomain of a legitimate domain.

Subdominator is a dependable and fast open-source command-line interface tool to identify subdomain takeovers. It boasts superior accuracy and reliability, offering improvements compared to other tools.

NMMAPPER. An online tool to find subdomains using Anubis, Amass, DNScan, Sublist3r, Lepus, Censys, etc. I tried NMMAPPER for one of the domains, and the results were accurate. Go ahead and give it a try for your research work.

Subdomains are free. With the right hosting plan, you can add subdomains at no additional cost. If it is that you have a large amount of subdomains on one domain, Google will not penalize you. It is rather easy to install/upload anything to a subdomain without impacting your main site.

Subdomains are used to expand the use of a single domain, these do not need to be purchased separately to your domain; if you own a domain then you can add a subdomain to this. This method is commonly used for Moodle and Totara site setups. An example of a subdomain is “elearning.mycustomdomain.com.”