Understanding IP History
Every website on the internet is hosted on a server identified by an IP address. When you type a domain name like google.com into your browser, the Domain Name System (DNS) translates that human-readable name into a numeric IP address that computers use to communicate. Over time, the IP address associated with a domain can change many times — and this history of changes tells a fascinating story about a domain's infrastructure evolution.
IP history refers to the chronological record of all IP addresses that a domain has been associated with. These records, primarily A records (mapping domains to IPv4 addresses) and AAAA records (mapping domains to IPv6 addresses), are collected through passive DNS monitoring. Every time a domain's DNS records change, that transition is logged, creating a comprehensive timeline of the domain's hosting history.
Why Do Domains Change IP Addresses?
There are many reasons why a domain's IP address might change over time. Understanding these changes provides valuable insight into what is happening behind the scenes with a website's infrastructure:
- Hosting provider migrations: When a website moves from one hosting provider to another — for example, from a shared hosting plan to a dedicated server or cloud platform — the IP address changes to reflect the new infrastructure.
- CDN adoption and changes: When a website starts using a Content Delivery Network (CDN) like Cloudflare, Akamai, or AWS CloudFront, the domain's IP addresses change to point to the CDN's edge servers rather than the origin server. Switching between CDN providers also triggers IP changes.
- Security incidents and DDoS mitigation: After a cyberattack or DDoS event, website operators frequently move their infrastructure to new IP addresses to shake off persistent attackers. Sudden IP changes can sometimes indicate security-related events.
- Geographic expansion: As companies grow and expand to serve users in new regions, they may deploy servers in additional data centers, leading to new IP addresses appearing in the domain's history.
- Server upgrades and maintenance: Routine infrastructure upgrades, data center migrations, and hardware changes all result in new IP addresses being assigned to a domain.
- Cloud provider changes: Migrating between cloud platforms (e.g., from AWS to Google Cloud, or from Azure to a private data center) results in entirely new IP address ranges.
Use Cases for IP History Data
Security Research
Security professionals use IP history to investigate suspicious domains, track the infrastructure of threat actors, and identify patterns that may indicate malicious activity. By examining the IP history of a domain involved in phishing or malware distribution, researchers can discover other domains hosted on the same infrastructure and map out an attacker's network.
OSINT and Intelligence Gathering
Open Source Intelligence (OSINT) analysts rely on IP history as a fundamental data source. It helps establish connections between seemingly unrelated domains, identify shadow IT infrastructure, and verify the ownership and operational history of online assets. Historical IP data can reveal relationships between organizations that share hosting infrastructure.
Competitive Intelligence
By tracking a competitor's IP history, businesses can gain insight into their technology stack, hosting decisions, CDN usage, and infrastructure investments. A migration to a premium cloud provider or the adoption of a new CDN can signal strategic shifts in a company's approach to performance and scalability.
Compliance and Due Diligence
For compliance teams and investigators performing due diligence, IP history provides a verifiable record of where a domain has been hosted. This is valuable for regulatory compliance, audit trails, and verifying claims about data hosting locations and jurisdictions.
How ip-history.net Works
Our tool leverages the Profundis.io DNS intelligence API, which maintains one of the largest collections of historical DNS data available. When you search for a domain on ip-history.net, we query the Profundis database for all historical A and AAAA records associated with that domain.
The results are enriched with GeoIP data, showing you not just the IP addresses but also the geographic locations and network information for each historical record. This enrichment helps you quickly understand where a domain's servers have been located over time and which hosting providers have been used.
Try it yourself — look up the IP history for popular domains like google.com, github.com, cloudflare.com, or amazon.com to see how their infrastructure has evolved.
Going Deeper with Profundis.io
While ip-history.net provides a free and easy way to look up IP history for any domain, Profundis.io offers a comprehensive DNS intelligence platform with unlimited access, advanced search capabilities, bulk lookups, API access, and detailed ASN and network analysis. For professional security researchers, OSINT analysts, and IT teams that need extensive historical DNS data, Profundis.io is the complete solution.
Related Tools
- About IP History — Learn more about this tool and how to use it
- ReverseIPs.com — Find all domains hosted on a specific IP address
- DNSTimeline.com — Visualize DNS record changes over time with an interactive timeline
- InternetLiveView.com — Real-time internet statistics and live data
- Profundis.io — Full DNS, Host, Certificate, and Whois intelligence platform