An expired SSL certificate is one of the most common causes of avoidable downtime. Your server is fine, your code is fine, and every visitor sees a full-page browser warning. Most leave. API clients refuse the connection entirely, so integrations break at the same moment.
Automatic renewal has made this rarer, not impossible. A renewal job fails after a server move, a DNS change breaks validation, a certificate on a forgotten subdomain was issued by hand two years ago. SSL certificate monitoring is the safety net for all of those.
What Uptimecheck checks
- The expiry date of the certificate served on every HTTPS monitor, read on every check.
- Days left on each monitor, amber under 30 days and red under 14.
- Certificates that expire within 14 days, listed under Needs attention on the overview.
- Reminders to your alert channels 30, 14, 7 and 1 day before expiry, and on the day.
- A failed check when the certificate is expired, untrusted or issued for another name.
Read our guide on SSL certificate expiry monitoring for a renewal checklist, and SSL certificate errors explained for what each browser warning means.
A typical case
The wildcard certificate for *.northwind.shop expires in 14 days. Renewal is automated, but the job has been failing quietly since the server migration last month. Uptimecheck sends a reminder to the team channel. Someone checks the renewal log, finds the broken DNS validation and fixes it on a Tuesday afternoon instead of during a Saturday outage. If your certificates renew automatically, a reminder means the renewal failed.
Certificates and domains go together
A certificate is only as good as the domain it sits on. If the domain registration lapses, the site goes down regardless of the certificate. Pair SSL monitoring with domain expiry monitoring, and watch your records with DNS monitoring so a validation record change does not surprise you.
For agencies managing many client sites
If you look after dozens of client websites, certificates are the thing that slips. Put every client site in Uptimecheck, group them in projects per client, and see which certificates need attention across all clients on one overview. When it does go wrong, a status page per client keeps the phone quiet, and client reports show each client their uptime every month.
A renewal checklist
- Know who owns renewal for every certificate, including old subdomains and client sites.
- Confirm automatic renewal actually ran after every server move or DNS change.
- Check that the renewed certificate is the one being served, not just the one on disk.
- Remove monitors for domains you no longer use, so real reminders do not get lost in noise.
Reminders give you time to work through that list calmly. The goal is that certificate renewal becomes routine maintenance instead of an incident.
Certificates on APIs and webhook receivers
Not every certificate sits on a public website. API endpoints, webhook receivers, admin panels and staging environments all have certificates, and an expired one breaks integrations without any visitor seeing a warning. Add an HTTPS monitor for each public endpoint so nothing renews on luck.
Reminders go to email, Slack, Microsoft Teams, Discord, Google Chat, Mattermost, Telegram, PagerDuty, ntfy, Pushover, webhooks and push notifications on every plan.
Plans start at €9 per month billed yearly or €12 billed monthly, excl. VAT, and SSL monitoring is included on every plan. Compare limits on the pricing page, or start a 14-day free trial without a card.