> For the complete documentation index, see [llms.txt](https://tools.osintnewsletter.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://tools.osintnewsletter.com/osint-tools/whoisology.md).

# Whoisology

| **Whoisology**   | **Quick Overview**                                                                                                      |
| ---------------- | ----------------------------------------------------------------------------------------------------------------------- |
| URL              | <https://whoisology.com/>                                                                                               |
| What it does     | Searches WHOIS records to identify domain ownership links, registration history and associated internet infrastructure. |
| How to use it    | Search a domain, email address, registrant name or organisation to discover related WHOIS information.                  |
| Cost             | Free with paid subscription options for expanded access.                                                                |
| Account required | No for basic searches. Yes for some advanced features.                                                                  |
| Cookies          | Mostly site functionality and session cookies.                                                                          |
| Ownership        | Acquired by WhoisXML API in mid-2018, which was founded by Jonathan Zhang.                                              |
| Use in Reporting | Supports domain attribution, infrastructure mapping and online identity investigations.                                 |

### What does Whoisology do?

Whoisology allows you to investigate domain registration information and discover relationships between domains, registrants, email addresses and organisations.&#x20;

The platform provides historical WHOIS data and reverse WHOIS capabilities, enabling you to identify patterns of domain ownership, connected infrastructure and potential links between online assets.&#x20;

**The lowdown:** Unlike basic WHOIS lookup services, it focuses on identifying connections between domains and registration records over time.

### How to Use:

**1. Search a domain name, registrant name, organisation or email address.**

<img src="/files/2vlHLZWp72Ka70Ykbamx" alt="" height="183" width="602">

**2. Review WHOIS records, historical ownership information and related domains.**

<img src="/files/whPlGw5jKnCFBTcgTjil" alt="" height="237" width="602">

<img src="/files/fn4VrMQJr0AWjvp441Nv" alt="" height="425" width="602">

**3. Map identified connections and corroborate findings with additional OSINT sources before reporting.**                                        &#x20;

### Cost

* [ ] Free
* [x] Partially Free
* [ ] Paid

Free with paid subscription options for expanded access.&#x20;

## Data Processing

### Account Required:

* [x] Yes
* [x] No

No for basic searches. Yes for some advanced features.

### Cookies:&#x20;

The site uses mostly authentication, security, and preference cookies from Google, plus one cookie from Whoisology.

### Use in Reporting

Whoisology is particularly useful for:

* Domain ownership attribution investigations.
* Cyber threat intelligence investigations.
* Fraudulent website and scam investigations.
* Brand impersonation and phishing investigations.
* Digital footprint and infrastructure mapping.
* Link analysis between online entities.

The book [Hunting Cyber Criminals: A Hacker’s Guide to Online Intelligence Gathering Tools and Techniques](https://onlinelibrary.wiley.com/doi/10.1002/9781119541004.ch9) references Whoisology as a service for analysing domain registration history and reverse WHOIS searches.&#x20;

| **Capabilities**                                                         | **Limitations**                                                                |
| ------------------------------------------------------------------------ | ------------------------------------------------------------------------------ |
| Performs reverse WHOIS searches.                                         | WHOIS data may be hidden through privacy protection services.                  |
| Identifies domains linked to the same registrant or organisation.        | Accuracy depends on the availability and quality of registration records.      |
| Provides historical WHOIS information.                                   | Historical records may be incomplete/unavailable.                              |
| Helps map relationships between online assets                            | Ownership information doesn’t always represent the true operator of a website. |
| Supports domain attribution investigations.                              | Requires additional verification before making attribution claims.             |
| Enables discovery of connected infrastructure and registration patterns. | Limited usefulness where domains use anonymous registration services.          |

### Summary

Whoisology is best used during the discovery, attribution and analysis stages of the OSINT workflow, helping investigators identify relationships between domains, registrants and online infrastructure. As always, findings should be corroborated with additional sources such as DNS records, certificate transparency logs and other threat intelligence platforms.&#x20;

### Ownership

Whoisology was originally co-founded by Ryan McKegney, but the business was acquired by WhoisXML API in mid-2018, which was founded by [Jonathan Zhang.](https://www.linkedin.com/in/jonathanmzhang/)

### Ethical Considerations

* Respect privacy regulations when handling personal WHOIS information.
* Avoid assuming a registrant is the direct operator of a website.
* Use WHOIS data as an investigative lead rather than definitive proof.
* Consider the legitimate use of privacy protection services.
* Ensure findings are independently verified before publication.

### Related Tools:

* DomainTools
* WhoisXML API
* SecurityTrails
* ViewDNS
* ICANN Lookup

#### Sources

<https://whoisology.com/>&#x20;

<https://whoisology.com/about>&#x20;

<https://osintradar.com/tools/whoisology>&#x20;

<https://domaininvesting.com/whoisology-acquired-by-whoisxml-api/>&#x20;

<https://www.linkedin.com/in/jonathanmzhang/>&#x20;