Certificate SAN Explorer

Connect to a TLS endpoint and list the DNS names published in its certificate Subject Alternative Name extension.

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Learn how to check certificate SANs, confirm whether a hostname is covered, and use SAN data to troubleshoot TLS errors and asset exposure.

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Learn what a subject alternative name is in a TLS certificate, why SANs matter for hostname validation, and how SAN data helps with discovery and troubleshooting.

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