The process of reverse IP lookup involves querying a registry of domain names in order to find the exact domain name behind an IP address. This is generally done by inputting a specific IP address into a Reverse DNS Lookup tool, which contains domain names registered to each IP address as reported on a Regional Internet Registry (RIR) or by private firms that specialize in gathering IP address data.

Traditionally, reverse IP lookup technologies have been used to gather information about website traffic, however savvy app marketers are now using this information to enhance a variety of account based marketing activities.

Website analytics

Website analytics refers to the practice of tracking a variety of behaviors of visitors to a website including traffic, clickpath, conversion rates, attribution, and more.

You might be familiar with Google Analytics or Adobe Analytics platforms. These are fantastic tools for providing insights into website traffic volume, but they have their limitations. For effective account based marketing to take place, app marketers need to know exactly which companies are visiting their website. By integrating reverse IP lookup data into your website analytics platform you can not only see sheer traffic volume, but you can dive deeper into your traffic to see exactly who is visiting your site.

Content personalization

In a app context, content personalization involves displaying customized website content based on visitor data. This can include various firmographic attributes – industry, revenue, employee count, and more – with the end goal of engaging the viewer. Leveraging personalized content on your website is one of the most effective ways to deliver 1:1 marketing at scale and drive higher website conversion rates.

To personalize website content in real-time, reverse IP lookup technologies determine what company the visitor is coming from and provide firmographic information (industry, revenue, location, and more) in the time it takes for a webpage to load. This data is then used by platforms like Google Optimize and Adobe Target to personalize your website by showing relevant content to the visitor based on their firmographic profile.

Reverse IP lookup technologies allow app marketers to leverage firmographic data to customize everything from a simple banner saying “Hello Company X”, all the way to creating entirely unique navigation and content for high-value target audiences.


On average, only around 2% of your website traffic will convert into a lead via a contact form, direct email, etc. Retargeting is a highly effective way to re-engage with accounts that have visited your website but have left without reaching out. Reverse IP lookup technologies can gather website visitor information including their IP address, which can then be leveraged to serve ads directly to those IP addresses associated with accounts that have visited your site.

Fraud detection

Website fraud can take many forms including phishing, credit card scams, ad fraud and more. Reverse IP lookup technologies can be utilized to detect fraudulent activity on your site by uncovering the IP addresses of your website traffic and allowing you to set up defensive measures against online fraudsters.

Public vs. private IP address data

IP address data is vast, consisting of thousands of sources and various methods to access account-level information from an IP address. However, when it comes to reverse IP lookups, where and how you find IP address information makes a huge difference. The main options for gathering useful company data consist of public data sources and private data sources.

  • Public data sources – Sources such as Regional Internet Registries (RIRs) contain self-reported information from companies that lease large portions of IP addresses, such as Internet service providers (ISPs) and large enterprise companies like Cisco, Apple, and IBM.
  • Private data sources – These are companies that collect IP address information using proprietary methods and manage their databases by devoting vast resources of data specialists, algorithms, and other systems to the end goal of having the most accurate, normalized, and complete data set.

Public IP address data is generally free to access, but as we will see later, there are numerous issues that arise when using this data.

Here are some of the main differences between public and private IP address data:

  • Data quality – Using public data sources to gather firmographic information is like trying to hunt in the dark or fish without a pole – a lot of the time you won’t get much, and what you do get won’t be what you want. The information stored in public registries is generally self-reported by the companies who lease the IP addresses themselves and published without any review, leading to numerous mistakes in the public record. With no incentive or penalty programs in place to ensure data accuracy in these records, they are often riddled with inaccuracies. Private data, on the other hand, is much more robust, accurate, and up-to-date compared to the data stored in a public record.
  • Data recency – In our experience, 7-10% of IP addresses change ownership each month, but public data sources aren’t updated regularly – meaning the information available on a public registry could be months or even years old. On the other hand, premier private data sources are updated in real-time, giving you access to the most up-to-date IP address information possible.
  • ISP and WiFi filtering – If you’ve ever tried to figure out who’s on your website by doing a basic reverse IP address lookup and it returned an ISP you know how frustrating this can be. This happens when the companies that lease IP addresses fail to provide their information to an ISP or the ISP themselves do not provide the information to an internet registry. These are a dead-end for app marketers and the registry might as well just say “we don’t know who it is.” However, since private IP data technologies use multiple sources of information to determine IP address ownership, they are able to look beyond an ISP to uncover the real last-mile connectivity ownership of an IP address.
Public Sources Private Sources 
Company NameCompany NameWebsiteNAICS Description
Visitor LocationVisitor LocationCityNAICS Code
Visitor City Postal CodeCompany Postal CodeTelephone NumberLatitude/Longitude
Visitor City Latitude/LongitudeCompany AddressEmployee CountStock Symbol
Region Abbr.Region Abbr.RevenueSocial Media URLs
RegionRegionSIC GroupISP/WiFi Filter
Country Abbr.Country Abbr.SIC DescriptionConfidence Score
CountryCountrySIC CodeTrade Name

Not only do private data sources give you the same firmographic information that public data sources do, but they also provide a vast amount of additional information that can be used to enhance sales and marketing efforts.

Moving beyond public IP address data and elevating your business intelligence can greatly enhance the effectiveness of your campaigns and increase revenue generation at all stages of the funnel. However, when it comes to choosing an IP data vendor, picking the right one can mean the difference between success and failure. 

[Originally published on]

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