IP Netblocks Owner Lookup | WhoisXML API

IP Netblocks Owner Lookup: Quickly Find Out Who Owns an IP Range

Just take an IP address (IPv4 or IPv6), a company name, or the autonomous system number (ASN) to get access to all corresponding IP ranges. For each range, IP Netblocks Owner Lookup provides IP netblock borders; first and last netblock update; organization or Internet service provider (ISP) name and address; abuse, administrative, and technical contact information; ASN and netname details; regional Internet registry (RIR); and more. Use this information to optimize your cybersecurity undertakings, uncover the infrastructure and footprint behind an IP address, enrich your marketing operations, and more.

9.5 million+IP Netblocks in total
48,000+Ranges updated daily
65,000+Unique ASNs

What Are IP Netblocks?

IP netblocks refer to series or ranges of successive IP addresses that are part of the same block, such as 8.8.8.0–8.8.8.255. RIRs assign IP netblocks to netblock owners, typically ISPs and large enterprises that require a sizable number of IP addresses.

What Are IP Netblocks?

Why Use IP Netblocks Owner Lookup?

  • Exhaustive

    IP Netblocks Owner Lookup retrieves data from one of today’s most comprehensive IP Netblocks WHOIS Database that contains information on more than 9.5 million netblocks and tens of thousands of unique ASNs and ranges refreshed daily.

  • Actionable

    Outputs from our IP netblocks lookup tool are formatted for intuitive data reporting with the most relevant ownership details readily available. The lookup reports can be easily shared with colleagues and relevant stakeholders via permanent URLs.

Practical usage

Bring Context to Your Cybersecurity Efforts

Bring Context to Your Cybersecurity Efforts

  • Learn more about the range of an IP address identified as malicious. With IP Netblocks Owner Lookup, you can immediately find out who is in charge of a given IP range and report abuse to relevant entities.
  • Correlate IP netblocks data with other sources of threat intelligence to build thorough attacker profiles and understand your network’s attack surface to thwart distributed denial-of-service (DDoS) and other attacks before these can halt business operations.

Make Informed Online Business Decisions

  • Study your netblock allocation to reduce concentration risks and dependencies on certain ISPs and hosting providers.
  • Correlate your web server logs with IP netblocks data to find out which networks your website traffic is coming from.
  • If you’re thinking about expanding your Web portfolio or preparing for a merger or an acquisition, you can easily find neighboring netblocks that might be available for purchase with IP Netblocks Owner Lookup.
Make Informed Online Business Decisions
Protect Your Business and Reputation

Protect Your Business and Reputation

  • You can use the ownership and location information available in IP netblocks to implement and enforce digital rights management (DRM) and URL filtering strategies.
  • Know if you are sharing your IP netblock with bad actors, which can cause your website to land on blacklists.
  • Find out if anyone is abusing any address in your dedicated IP range.
IP Netblocks WHOIS Database

Find out more about the largest IP Netblocks WHOIS Database

All of our IP netblocks data is also accessible in our extensive database, available in JSON or CSV with consistent and unified ranges.

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IP Netblocks Lookup | WhoisXML API

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