Reverse NS products to reveal all connected hostnames | WhoisXML API

Reverse NS products to find all domains that use the same nameserver

By using our reverse NS services, you can identify other domains that share your nameserver or use the same hosting company.

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500 free API requests. No credit card required.

32 Billion+Domains and subdomains
BillionsNS records
52,000+Satisfied customers
14+Years of data crawling

Our reverse NS product line includes:


Our easy-to-use graphical user interface (GUI) tool returns a comprehensive list of domains that use the same nameserver or host.

Reverse NS Lookup | WhoisXML API
Reverse NS API | WhoisXML API


One API call helps you establish all domains with a common nameserver as well as the matching timestamp for each domain.

DNS Database Download

Our DNS database contains billions of historical records and can be downloaded in a user-friendly and well-parsed comma-separated values (CSV), making it easily compatible with virtually any existing application.

DNS Database Download | WhoisXML API


  • Exhaustive and up-to-date

    Our passive DNS database covers all the connections between NS records and billions of domains and subdomains.

  • Flexible integration

    All of our nameserver records are adequately parsed and formatted for use as-is with your applications. The data is always presented with adequate formatting.

Product Usage

  • Overblocking Prevention

    Track the domains you share nameservers with, including hosts that might be blocked, which could negatively affect your domain reputation and website accessibility.

  • Domain Inventory

    Don’t overlook any of the domains your company owns. Our reverse NS solutions let you trace domain associations you may not even know existed.

  • IoC List Expansion

    Identify all indicators of compromise (IoCs) and potentially related artifacts, even if they haven’t been publicized.

  • Dangling Property Identification

    Identify web properties that have been left dangling or forgotten, so you can secure them from compromise and avoid threats like website defacement.

Reverse NS Overview | WhoisXML API

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