Find All Subdomains (2025)

FAQs

How do I query DNS for all subdomains? ›

Using a terminal and the command nslookup is the most effective way to search a domain's DNS records. On almost all operating systems, this command works perfectly and displays all DNS records for the domain. To show how to use the command, here's a sample nslookup command for each record type.

Characteristics and Parameters of a Subdomain

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.

Subdomain enumeration is the process of finding #subdomains of a particular domain. Subdomain Finder is a useful tool to help discover website subdomains. They can be used for a variety of purposes, including website reconnaissance, #vulnerability assessment, and #penetration testing.

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.

By default, the domain and its subdomains are part of the same DNS zone, i.e. they are hosted on the same web server. You also have the ability to create a delegation, in order to redirect one or more subdomains on another server.

Checking DNS records using the command line

The most efficient way to check DNS records of the domain is to use a terminal with the command nslookup. This command will run on almost all operating systems (Windows, Linux, and macOS).

By search engines

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”.

The most common subdomain is “www” or “world wide web.” The subdirectory points users to the main directory of a website—in other words, where your homepage and other core pages live. Other subdomains work to create distinct parts of a site. For example, Google's root domain is www.google.com.

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.

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

What are the disadvantages of subdomains? ›

Cons of Subdomains

This can result in your SEO efforts, link juice, and growing authority profile getting diluted instead of working together to contribute to your main site and all of its pages and content as one.

1 Answer. Yes, you own and control the entire namespace below the domain you purchase, because DNS is hierarchical. Creating mail.example.com and blog.example.com is just a matter of adding entries to the DNS zone that you control.

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.

Go to GA4 admin > Data Streams > Select your web data stream > Configure Tag Settings > Show More > List unwanted referrals and then enter your main domain there. For example, if your subdomains are subdomain1.example.com and subdomain2.example.com, then enter example.com in the settings of GA4.

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.