Reveal all the domains that use the same mail server

By using the Reverse MX service you can identify spamming, phishing and other poor reputation sites on your host.

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100 free requests monthly. No credit card required.

Reverse MX product line includes


Just take the mail server and do a quick Reverse MX Lookup to reveal all the domains that use the same mail server.

Reverse MX Lookup | Whois XML API
Reverse MX API | Whois XML API


With a single API call, make sure that your website does not share the mail server with any suspicious or blacklisted domains - hosts with a dubious reputation may affect email delivery.

DNS Database Download

The passive DNS database is a large Historic DNS repository with 2 billion hostnames and hundreds of billions of Historic DNS Lookups. We offer an exhaustive and properly parsed passive DNS database in the format of an MYSQL dump or a CSV file that can be easily processed by your application.

DNS Database Download | Whois XML API


  • Сomprehensive & up-to-date

    We provide service based on the world’s largest constantly updated database with 1,473,142,430 domains and subdomains, 142,703,533 MX records updated daily.

  • Fast response & easy integration

    A fast and easy-to-use API for quick access to the largest database. All the results are duly parsed and normalized to a consistent format such as JSON and XML for easy integration with your business processes.

Reverse MX Overview | Whois XML API

Get 100 free credits monthly. No credit card required.

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