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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risk score · threat categories · sources · age · confidence — in one request

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Domains Indexed

Passive

<0s

Response Time

Daily

Updates

Capabilities

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.

Applications

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.

Support

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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