SANs checker
See every name a certificate covers, its Subject Alternative Names (SANs), and where each one points.
What the result shows
The first row: the domain you checked and the addresses it resolves to. Every other name is compared with it.
The name points to the same address, or is an alias of the domain, so it is served together with it.
The name points somewhere else, probably another server or service, where the certificate has to be installed again after every renewal.
The name has no DNS record right now. If it is no longer used, leave it out of the next certificate.
It reads the certificate from port 443 of the domain, then looks up to 40 of its names in DNS (wildcards can't be looked up). Nothing is connected to on those names, and nothing is stored.
Learn more: name mismatch errors