SSL Certificate Monitoring
Never let an expired certificate take your site offline
SSL certificate monitoring tracks your certificate expiry and validity, giving you days of warning before an expiry causes browser security warnings that drive away your visitors.
Expiry countdown
Know exactly how many days remain on your certificate at all times, with amber warning at 14 days and red at 7 days.
Validity verification
Confirm the certificate is valid for your specific domain, catching wildcard mismatches and subdomain coverage gaps.
Renewal failure detection
Detect when automated renewal (Let's Encrypt / certbot) ran but failed to reload the web server with the new certificate.
Hourly checks
SSL is checked every hour alongside your other services, giving you a complete picture of your security posture.
Why certificates expire unexpectedly
Automated certificate renewal via Let's Encrypt and certbot is reliable when properly configured — but it fails silently when conditions change. Common failure modes: disk full (renewal generates the new certificate but cannot write the files), permission changes after a server update, nginx or Apache unable to reload cleanly after renewal, and cron jobs that stop running after a server migration. Each of these produces a certificate that expires without a new one being deployed.
The browser security warning impact
An expired SSL certificate causes every major browser to show a full-screen security warning with no obvious way to proceed for most users. The effective result is identical to your site being completely down — perhaps worse, because the warning implies your site has been compromised. Recovery requires deploying a new certificate and waiting for DNS caches to clear, which can take 30-60 minutes. SSL monitoring gives you 7-14 days of warning to renew before this happens.
Multi-domain and wildcard certificates
A wildcard certificate (*.example.com) covers all subdomains but expires all at once. If your wildcard expires, every subdomain shows a security warning simultaneously. Add an SSL check for each customer-facing subdomain — api.example.com, app.example.com, www.example.com — so expiry warnings are visible for each entry point independently.
Try SSL Certificate Monitoring now — free
Create your status page and start monitoring in under 5 minutes. No billing, no lock-in. Live for 7 days.
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