Check the SSL/TLS certificate of any domain — issuer, validity dates, days until expiry and subject alternative names.
An SSL/TLS certificate is what makes a site HTTPS: it proves to the browser that the server is who it claims to be, and it encrypts the traffic between the two. Certificates expire, and an expired certificate triggers a browser warning that drives visitors away. This tool connects to the domain on port 443, reads the certificate and shows you the details.
The check runs from the server, not from your browser. That means it sees the certificate as any visitor on the internet would see it — not a cached or locally trusted version. It shows the subject (the domain), the issuer (the certificate authority), the validity window, the number of days remaining, the serial number and the SAN (Subject Alternative Names), which lists every domain the certificate covers.
The connection is opened, the certificate is parsed, and the result is returned. Nothing is stored.
It reads the server certificate, not the intermediate or root. The issuer field tells you who signed it.
Subject Alternative Names — the list of domains the certificate is valid for. A certificate for vai.la might also cover www.vai.la.
Because the current date is past the "Valid until" date. The certificate needs to be renewed.
Only if the domain resolves from the internet and port 443 is open. Internal-only domains are not reachable from this server.
Yes. A few checks per minute is fine for normal use.
Vai.la turns any URL into a short link with click statistics, QR Code and your own biolink.
Vai.la is not responsible for how the tools are used or for decisions made based on their results.