Subdomain Finder
Find all subdomains in one click for free
Trusted by 1M+ SEO professionals since 2013
What is a Subdomain Finder?
A Subdomain Finder is a tool that discovers and lists all subdomains associated with a primary domain. In addition to subdomain URLs, the tool provides general data on each one, including traffic forecasts, traffic share, the number of keywords, and more. This tool helps you gain a comprehensive view of a website’s architecture and ensures that all subdomains are optimized and secure.
Get a list of all subdomains with the main metrics
Location
Analyze subdomain performance across any location. Select any of the 190 countries to access country-level data.
Date
Get comprehensive research reports for the selected month. Access historical data to get detailed information for any past month going back to February 2020.
Traffic share
The tool shows the percentage of traffic a subdomain brings to the analyzed website. This metric demonstrates the traffic share for the selected location and period.
Total traffic
The tool shows the subdomain's organic traffic volume. SE Ranking calculates the expected click-through rate, search volume, and current keyword rankings to estimate this value.
Total traffic cost
This metric indicates the estimated cost of organic traffic a subdomain gets by targeting all discovered keywords. The tool displays cost in the equivalent of Google Ads prices.
Keywords total
The total number of keywords a subdomain ranks for in its organic search. Click through to get more data on each keyword: traffic, difficulty, search volume, competition and SERP features.


Make sure your subdomains are secure
Regularly perform technical checkups and quickly fix any issues
More tools for subdomain management
Evaluate subdomain organic performance
Analyze your subdomain’s keywords, their rankings and the traffic they attract, competitors, and even PPC ads.
Check subdomain health and security
Assess your subdomain’s technical SEO, including security, crawling, UX, and other issues, and receive a list of tips for fixing them.
How our subdomain finder works
Subdomain Finder scans the DNS records and supplementary databases to analyze the domain’s hierarchy. Our subdomain scanner checks:
DNS records (NS, MX, TXT, AXFR)
DNS enumeration
SSL certificates
HTML links
Search engine results
Reverse DNS for target IP addresses
How to use our subdomain scanner
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.
How reliable is our subdomain checker
Subdomain scanner ensures the highest accuracy of results. It aggregates relevant information from search engines and supplementary databases and sends additional requests to domain service providers to get the most complete and up-to-date results. The scanner is secure; we don’t save or publish any information about checked domains and their subdomains.
How to find subdomains?
There are several ways to find subdomains:
Manually, by using the site:* operator in Google
By checking DNS records using the nslookup command
By using our online subdomain scanner or similar tools
Can a subdomain be taken over?
Subdomain takeover happens when a subdomain points to a non-active external service, but the CNAME used for that service is still in the DNS records. Hackers can set up a virtual host for the subdomain and gain control over it.
How to check a subdomain’s DNS records?
You can find DNS records using the nslookup command in the command line. It shows all DNS records for a given domain, including a list of subdomains. The command works for Windows, Linux, and macOS operating systems.
Is a subdomain a separate site?
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
How are subdomains displayed on Google?
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.
Is WWW a subdomain?
Technically, yes. You can find it among other subdomains in the search results, but it often redirects to the main domain. When the Internet was first created, the www. prefix was used to distinguish sites that use the Internet protocol. Today, some hosting providers automatically create the WWW subdomain for all sites and set up a redirect.
Can subdomains be hidden?
Yes, subdomains can be hidden. There are several ways to do this:
Hide it from crawlers using the disallow directive in the robots.txt file
Hide it from indexing—use the noindex or none directive in the robots meta tag in the HTML code of the page
Set the X-Robots-Tag HTTP headers to noindex or none on the subdomain server
How many subdomains can a domain have?
Theoretically, there is no limit to the number of subdomains, but some DNS servers set restrictions. For example, GoDaddy limits users to 500 subdomains.
Can subdomains be hidden from scanning tools?
It is impossible to hide a subdomain from scanning completely. Subdomain checkers use publicly available DNS registers to find information. But even if the scanner has detected a subdomain, it does not necessarily mean that the page is publicly accessible—its content can be hidden.
There's more to discover about your subdomains
See everything that matters for your subdomains analysis—traffic insights, SEO health, competitor data, growth potential, and more.
Sign up for free for more important insights on your subdomains