Find All Subdomains (2024)

FAQs

Is there a way to find all subdomains? ›

By search engines

Search engines like Google supports various advanced search operators to refine search queries. These operators are often referred to as Google Dorks. We can use site: operator in Google search to find all the Subdomains that Google has found for a Domain. Lets take an example on “site:vulnweb.com”.

A domain can have up to 500 subdomains. You can create multiple levels of subdomains such as store.product.yoursite.com, test.forum.yoursite.com, etc. Each subdomain can be up to 255 characters long, but for multi level subdomains, each level can only be 63 characters long.

Google's search operators make it easy to narrow down the search to find more subdomains. We can use the "site" operator in the search bar to find all the subdomains that Google has indexed for a domain. Google also supports the minus operator to exclude any subdomains we are not interested in.

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.).

subfinder is a subdomain enumeration tool written in the Go programming language. Subfinder is used for discovering passive subdomains of websites by using digital sources like Censys, Chaos, Recon. dev, Shodan, Spyse, Virustotal, and many other passive online sources.

As long as you use them correctly, subdomains are fine for your SEO performance.

Your subdomain reputation(s) can impact base domain reputation, but the impact between subdomains will be small. Subdomains are not a way to avoid a bad domain reputation. Instead, they will help differentiate your traffic while maintaining a clear relationship with your main domain.

The short answer is yes, Google can and will index and rank subdomains unless you explicitly take steps to ensure they're excluded from its index. Google's entire business model is based on discovering content. The same goes for all search engines.

Which Google Dork helps us to find subdomains? ›

One of the benefits of Google Dorking is that it can be used for subdomain enumeration. This is done by searching for the "site:" operator in Google, followed by the target domain.

Subdomain takeovers are a common, high-severity threat for organizations that regularly create, and delete many resources. A subdomain takeover can occur when you have a DNS record that points to a deprovisioned Azure resource. Such DNS records are also known as "dangling DNS" entries.

There are some subdomains that are defined for virtually every domain name, such as www, and others that are very common, like shop or mail. But by going through and trying a DNS query using `dig`, `nslookup`, or `host` for as many possible subdomains, you might find some hidden ones.

While Nmap is primarily used for network mapping, it can also be used for subdomain hunting. Nmap uses various techniques, such as port scanning, to identify active subdomains and gather information about them.

To identify DNS entries within your organization that might be dangling, use Microsoft's GitHub-hosted PowerShell tools "Get-DanglingDnsRecords". This tool helps Azure customers list all domains with a CNAME associated to an existing Azure resource that was created on their subscriptions or tenants.

Optimize Your Subdomains & Subdirectories for SEO

Both can be SEO-friendly. Whether you decide to use subdomains or subdirectories, you need to optimize them for the best chance of ranking in search engines.