How to check when an SSL certificate expires (before it takes your site down)

An expired SSL certificate is one of the most avoidable outages there is, and one of the most common. The certificate is valid right up until the moment it is not, and then every visitor gets a full-page browser warning instead of your site. No gradual decline, no warning email unless you set one up. Just off.

Why certificates lapse

Most certificates last 90 days now, and the window is only getting shorter. Auto-renewal helps, until it does not: a renewal job that silently fails, a DNS change that breaks validation, a certificate on a load balancer that nobody remembered. The person who set it up has often moved on by the time it expires.

How to check an expiry date

You can check any site's certificate in seconds with our free SSL certificate checker: enter the domain and it shows the expiry date, who issued it, and how many days are left. It is worth spot-checking anything important, especially after a hosting or CDN change.

For your own sites, checking once by hand is not a plan. Diaries get forgotten and 90 days comes around fast. The reliable approach is to have something watch the expiry date continuously and warn you well before the deadline, while there is still time to fix a stuck renewal calmly.

Build the reminder in

VigilVault reads the certificate on every check and flags it as the expiry approaches, so a lapsing certificate becomes a heads-up days in advance rather than a Monday-morning outage. It is the same monitor watching your uptime, so there is nothing extra to run.

Check a certificate now with the free tool, or have VigilVault keep an eye on yours.