Identify who is hosting a particular domain name or website

A domain has a number of records associated with it, and a DNS server can be queried to determine the IP address of the primary domain (A record), mail servers (MX records), DNS servers (NS nameservers) and other items, such as SPF records (TXT records). This is a REST API that performs DNS queries via simple HTTP requests, returning your results as JSON/XML-encoded objects.

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500 free credits monthly. No credit card required.

1.2 billion+Domains and subdomains
142,703,533MX records updated daily
196,463,291NS records updated daily
99.5%IP addresses in use covered

Benefits

  • Displays the DNS information critical for identifying who is hosting a particular domain name or website.

  • Determines the Mail Servers for Particular Domain. Use this API to find out what server(s) accept email for a specific domain by doing an MX record lookup.

  • Determines the IP address of the primary domain (A record), mail servers (MX records), DNS servers (name servers) and other items such as SPF records (TXT records).

  • Determines the SPF record for a domain by looking up its TXT record to see if the domain tries to restrict who can send email using the domains.

Useful for detecting or dealing with cybercrime or network security issues.

Useful for detecting or dealing with cybercrime or network security issues.

DDoS attack prevention

Even more violent than spam is the dreaded DDoS attack, which is basically a security attack on your web site from dozens or even hundreds of IP address simultaneously. If you suddenly noticean unusual amount of traffic, then you may want to conduct areverse DNS lookup and get to the root of it before it becomes a problem, especially if the traffic is originating from a group of similar IP addresses.

Anti-Spam solutions

Prevent spam attacks from aparticular web server or IP address. When your site is attacked by spam repeatedly, obtain the IP address(es) of the attackers and then use a reverse DNS lookup tool to obtain site registration informationof that IP address.

Penetration testing

Security penetration testers and researchers will use information collected from DNS to expand their knowledge of an organization’s information technology infrastructure and from that knowledge begin to understand the attack surface.

DNS Database Download

Get access to the biggest Passive DNS Database

The passive DNS database is a large Historic DNS repository with 2 billion hostnames and hundreds of billions of Historic DNS Lookups. Our comprehensive passive DNS database allows finding out all historical DNS data points for any hostname and ip address.

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DNS Lookup API | Whois XML API

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Enterprise API Packages

API access through WhoisXMLAPI can be purchased as an annual subscription. The access pricing is based on the number of queries, which is measured monthly with per-minute rate limits. The pricing structure gives predictability to business planning and solution architecture.

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