Free Subdomain Intelligence Tool
Find Subdomains of Any Domain
Search a large Certificate Transparency-based hostname index and see subdomains that have been observed, including their first-seen dates when available.
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With first-seen date0
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Host types0
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Host type breakdown
Intelligence summary
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Discovered hostnamesCertificate Transparency observations
| # | Hostname | Type | First seen | DNS | Action |
|---|
No subdomains match the current filter.
Important: An indexed hostname means it was observed by the underlying data sources; it does not guarantee that the host is live today. This tool is intended for legitimate domain research, asset inventory, and security awareness. Results are provided by crt.name.