Domain Intelligence Website

SecurityTrails

SecurityTrails is a domain and internet intelligence website and API platform for DNS records, WHOIS data, subdomains, SSL certificate history, IP information, and organization-focused security research.

Official site

securitytrails.com is the main public website for SecurityTrails.

Core use

Users look up domain, DNS, WHOIS, SSL, IP, subdomain, and company-related information for security research and asset discovery.

API model

The official documentation describes a read-only REST API exposed at api.securitytrails.com/v1.

SecurityTrails provides domain, DNS, WHOIS, subdomain, certificate, IP, and company-related intelligence through a web platform and API.View logo asset on SecurityTrails documentation

What SecurityTrails is

SecurityTrails official site is a domain and internet intelligence service for investigating public infrastructure. Its documentation describes products that enrich data, search for information, and help users find security-relevant details about organizations.

Domain intelligence

SecurityTrails is especially useful when a user starts with a domain name and needs surrounding context. Domain records can connect a hostname with current DNS data, related statistics, nameservers, mail records, IP addresses, certificates, and other clues that help explain how a website or organization is exposed online.

DNS and subdomain data

The API reference includes endpoints for current domain data and subdomain lists. Subdomain discovery is important because forgotten staging sites, old apps, regional hostnames, and third-party integrations can reveal parts of an organization's public footprint that are easy to miss in an internal inventory.

WHOIS and history

SecurityTrails documentation includes current WHOIS data and WHOIS history endpoints. Historical ownership and registration data can help researchers understand how domains changed over time, though WHOIS privacy, redaction, transfers, and proxy services mean the data should be treated as investigative context rather than proof of control.

DNS history and certificates

Historical DNS and certificate records help analysts see where a domain pointed before, which infrastructure it shared, and whether related names or certificates suggest a broader pattern. This can support phishing investigations, incident response, brand-protection work, and infrastructure mapping.

API workflows

The SecurityTrails API is read-only and uses REST-style HTTP methods. Security teams can use it to enrich SIEM events, automate reconnaissance, support asset discovery, and connect domain or IP indicators with DNS, WHOIS, certificate, and company context.

Who uses SecurityTrails

SecurityTrails is used by threat-intelligence researchers, SOC teams, incident responders, penetration testers, fraud analysts, brand-protection teams, developers, and OSINT investigators. A small investigation might check one domain, while an enterprise workflow might enrich thousands of assets through the API.

Why it matters

Domains are often the thread that ties internet activity together. Attackers register lookalike domains, companies forget old subdomains, and infrastructure changes leave historical traces. SecurityTrails matters because it helps turn scattered DNS, WHOIS, certificate, and IP clues into searchable context.

WHOIS domain data

Data pulled: May 23, 2026View current WHOIS record

Domain: securitytrails.com
IP address: 172.66.41.38
Registrar: GoDaddy.com, LLC
WHOIS server: whois.godaddy.com
Referral URL: http://www.godaddy.com
Created: June 21, 2017
Updated: June 22, 2025
Expires: June 21, 2026
Nameservers: rick.ns.cloudflare.com (108.162.193.139); hope.ns.cloudflare.com (108.162.192.163)
Domain status: clientDeleteProhibited https://icann.org/epp#clientDeleteProhibited; clientRenewProhibited https://icann.org/epp#clientRenewProhibited; clientTransferProhibited https://icann.org/epp#clientTransferProhibited; clientUpdateProhibited https://icann.org/epp#clientUpdateProhibited
Contact privacy: Registrant contact is listed as Registration Private through Domains By Proxy, LLC.

Key concepts

Domain intelligencestructured information about domains, DNS records, certificates, registration data, and related infrastructure.
Passive DNShistorical or observed DNS data collected without directly querying the target infrastructure in real time.
WHOIS historypast domain-registration records that can help explain ownership, registrar, or contact changes.
Subdomain enumerationfinding hostnames under a domain that may reveal applications, services, or forgotten assets.

Website features

Look up current domain records and related DNS statistics.
Find subdomains associated with a hostname.
Retrieve current and historical WHOIS information for domains.
Use DNS history, certificate data, IP information, and search endpoints in security workflows.

Common misconceptions

DNS or WHOIS context does not prove malicious intent; it is investigative evidence that needs corroboration.
A discovered subdomain is not automatically vulnerable, but it may deserve ownership and exposure review.
WHOIS privacy and proxy services can hide or simplify registration details, so ownership conclusions should be cautious.
Domain intelligence tools complement scanners and logs; they do not replace internal asset management.

Open questions

How can domain-intelligence platforms keep historical data useful while respecting privacy and redaction requirements?
Which signals best connect domains, certificates, IPs, and companies without over-attributing unrelated infrastructure?
How should defenders prioritize huge subdomain and DNS-history result sets without drowning in noise?
Will AI-assisted investigations make domain pivots easier, or will they increase the risk of unsupported attribution claims?