How to check when an SSL certificate expires
Every certificate has an end date, and a site stops loading the day after. Here are three ways to see that date, from quickest to most detailed.
1. With a free online check
Enter the website address in the KeenCrow checker. The result shows the expiry date, how many days are left and who issued the certificate, along with whether the site itself answers. It needs no account.
2. In your browser
- Open the website and click the padlock or the site information icon next to the address.
- Choose the option that mentions the connection or the certificate.
- Look for the line called "Expires on", "Valid until" or "Not after".
The exact wording differs between browsers and changes from time to time, but the date is always in the certificate details.
3. From the command line
If you have OpenSSL installed, this prints the end date of the certificate a server presents. Replace yourdomain.com with your own domain in both places.
openssl s_client -connect yourdomain.com:443 -servername yourdomain.com | openssl x509 -noout -enddate
Checking once is not enough
Most certificates renew automatically, and most surprises happen when that renewal quietly stops. Looking today tells you about today. KeenCrow reads the certificate on every check and emails you 7, 3 and 1 days before it expires, so a failed renewal is caught while there is still time.