Threat Intelligence

Subdomain Scanner

Discover and enumerate subdomains

Find hidden attack surface with passive subdomain enumeration. Discover subdomains from certificate transparency, DNS records, and our historical database.

Scan Subdomains API Documentation

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Get instant threat analysis with risk scores, threat categories, and detailed reports.

5B+

Subdomains Indexed

100%

Passive

<5s

Response Time

Daily

Updates

Key Features

Everything you need to protect your infrastructure and users

Passive Enumeration

Discover subdomains without active scanning using public data sources.

Certificate Transparency

Find subdomains from SSL certificate logs.

DNS Records

Extract subdomains from SPF, DMARC, and other DNS records.

Historical Data

Access our database of historically observed subdomains.

Live Verification

Check which discovered subdomains currently resolve.

Threat Detection

Flag subdomains that resolve to known malicious IPs.

Use Cases

How security teams use this tool

Attack Surface Discovery

Find forgotten subdomains that may be vulnerable.

Security Assessment

Enumerate subdomains during penetration testing.

Brand Monitoring

Discover unauthorized subdomains on your domain.

Threat Hunting

Find infrastructure related to suspicious domains.

Frequently Asked Questions

How do you discover subdomains?

We use passive techniques including certificate transparency logs, DNS records, search engines, and our historical data to find subdomains without active scanning.

Is subdomain scanning legal?

Our passive enumeration is legal as it only queries public data sources. We do not perform active scanning or brute forcing.

How many subdomains can you find?

We typically find thousands of subdomains for large organizations. Results vary based on the domain's size and our data coverage.

Do you check if subdomains are live?

Yes, we verify which discovered subdomains currently resolve and provide their IP addresses.

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