Find domains linked to SOA, TXT, or CNAME records | WhoisXML API

Find DNS record-to-domain connections in seconds

Look for domain names linked to SOA, TXT, or CNAME records instantly with Reverse DNS Lookup. Try our lookup tool now.

50 Billion+Domains and subdomains
116 Billion+DNS records
7,596+gTLDs and ccTLDs tracked
52,000+Satisfied customers

Why Use Reverse DNS Lookup?

  • Diverse inputs

    Gather all associated domain names using a DNS record as the starting point—SOA, TXT, or CNAME.

  • Market-leading DNS coverage

    Leverage our comprehensive DNS database, containing billions of recorded events, with every lookup.

  • Fast and easy

    Produce lookup reports in seconds, with options to share via a link or export as JSON for a more detailed review.

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Practical Usage

  • Detection of DNS issues

    Identify misconfigured CNAME records and hidden dependencies to prevent subdomain takeovers and malicious redirections.

  • DNS-based asset discovery

    Reveal domains linked to SOA, TXT, or CNAME records to map overlooked assets and connections in your DNS ecosystem.

  • Threat actor attribution

    Find domains linked to threat actor campaigns, phishing operations, or malware delivery by analyzing specific TXT, SOA, or CNAME records.

  • Spam prevention

    Ensure sender legitimacy and detect spam-associated domains to strengthen email authentication and filtering.

Reverse DNS Lookup | WhoisXML API

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