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SSL Certificate Expiry: Check Renewal Before HTTPS Breaks

A certificate expiry date is an operational deadline. Renew early, verify the live certificate, and make sure every hostname presents the intended chain.

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An expiry date is only the first check

A certificate checker reads the certificate currently presented by a hostname. Check its expiry, issuer, subject names and chain. Renewing a certificate in an account is not enough if the web server still presents an older file, a missing intermediate, or a certificate for another hostname.

Test both the canonical hostname and alternate www/non-www host after any TLS change. Redirects happen after a TLS handshake, so a bad certificate on the source host can stop visitors before the redirect runs.

Data center servers representing HTTPS certificate delivery
The certificate a browser receives depends on the live hostname and server configuration.

Renew, deploy, then verify the final host

Use the SSL certificate checker to inspect the live result, the Certbot and Let’s Encrypt guide for automated renewal, and the OpenSSL CSR guide for a managed-certificate workflow.

  • Set alerts well before expiry, not on the final day.
  • Confirm renewal reloads the web server or proxy.
  • Verify the exact public hostname from an external network.
  • Keep HTTP-to-HTTPS redirects direct after certificate validation.

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