/ ssl monitoring
SSL certificate monitoring that warns before a certificate expires
An SSL monitor connects to your host, reads its certificate and checks it the way a browser would. You hear about an expiry days before it happens, and about a broken chain or hostname the moment a check finds it, instead of from a visitor’s browser warning.
SSL monitors are on every plan, free included. The SSL expiry monitoring guide walks through the setup, and the free SSL checker reads a certificate once, without an account.
What an SSL monitor checks
- A warning before expiry
- Choose how many days ahead to hear about it, from 1 to 365; 14 unless you change it. Fettle checks the certificate on every probe, at the monitor's own interval, and a daily sweep sends the expiry warning once, when the certificate enters that window.
- Renewals re-arm it
- When the certificate is renewed, the warning re-arms for the new one, so each certificate warns you once, not every day.
- Broken certificates
- An expired certificate, a chain that does not verify or a hostname that does not match marks the monitor down, opens an incident and alerts you.
- Expiring soon, still working
- With less than 14 days left, the monitor shows as degraded: it still counts as up, but it stands out on the dashboard.
- Every expiry in one list
- Sort your monitors by certificate expiry, soonest first, in the dashboard, the API or the MCP server, so “which certificates expire this month” is one question for your agent.
- Any port
- Port 443 by default, or the port your mail server, database proxy or internal API listens on.
Where the warning goes
The expiry warning and incident alerts go to the monitor’s channels: email and Telegram on every plan, and Slack, Discord or a webhook from Plus. A webhook delivery carries the days left, the expiry date, the issuer and the subject, so a script can open a ticket or start a renewal.
Plans
An SSL monitor is a monitor like any other, checked from one region on the interval you pick. The free plan covers 20 monitors every 3 minutes from 1 region, SSL ones included. Every plan and limit is on the pricing page.