Features

SSL certificate monitoring and expiry alerts

Uptimely sends SSL certificate expiry reminders by reading your certificate on every check and alerting you when the days left drop below the lead time you set. Add a rule such as Expires In Days less than 30, and the monitor changes status and opens an incident while there is still time to renew. It also checks whether the certificate is trusted and whether it has already expired.

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An expired certificate takes a site down as completely as a crashed server, and every browser makes sure each visitor sees the warning. Certificates renew automatically most of the time, which is exactly why a broken renewal goes unnoticed until the day it matters.

An SSL Certificate monitor is its own monitor type, separate from a website monitor. Out of the box it goes offline only when it cannot read a certificate at all. An expired or untrusted certificate is detected on every check, but it pages nobody until you add a rule for it, and the steps below cover the two rules most teams start with.

How the expiry reminders work: there is no fixed reminder schedule, because you choose the lead time. Each check reads the days and hours the certificate has left, and a rule such as Expires In Days less than 30, or Expires In Days less than 14, is met on the first check that falls below it. The monitor changes status on that check, and opens one incident once it has failed the monitor's failure threshold of consecutive checks (2 by default, adjustable from 1 to 10 per monitor). That incident stays open while the rule keeps matching and resolves on its own once a renewed certificate no longer does. The reminder reaches your team on the channels you have set up, which can be email, SMS, Slack, Discord and browser push, and an on-call policy can phone the person on duty.

What an SSL certificate monitor checks

Checked on every run of an SSL Certificate monitor. A rule in the monitor's criteria decides which findings change its status and open an incident.
Check	What it catches	Without a rule	Rule that alerts on it
Certificate can be read	The host is unreachable, the port is closed, or the TLS handshake never completes	The monitor goes offline	None needed
Days left	A renewal that stopped working, weeks before the certificate lapses	Checked, no alert	Expires In Days, Less Than, 30
Hours left	The final day before expiry, useful for short-lived certificates	Checked, no alert	Expires In Hours, Less Than, 24
Trusted chain	A self-signed certificate, a missing intermediate or an untrusted issuer	Checked, no alert	Is Not A Valid Certificate
Hostname match	A certificate issued for a different host than the one you entered	Checked, no alert	Is Not A Valid Certificate
Already expired	A certificate past its end date that is still being served	Checked, no alert	Is Not A Valid Certificate

How expiry alerts compare

When an SSL certificate expiry alert fires. Each vendor row quotes the vendor's own page, linked with the date it was read.
Service	Expiry alert	Source
Uptimely	Fires at the lead time you set, in days or in hours, through a rule such as Expires In Days, Less Than, 30. Available on every plan, Free included.	Uptimely docs
UptimeRobot	Its pricing page: "Alerts you 30/14/7 days before your SSL certificate expires."	Vendor page, read 2026-10-26
Better Stack	Its docs: SSL certificate monitoring "is built into uptime monitors and keyword monitors", and "Certificate expiration alerts require a paid plan."	Vendor page, read 2026-10-26

What you get

Days and hours left. Every check reads how long the certificate has left, in days and in hours, and a rule can act on either.
Trust and hostname checks. Every check verifies that the certificate is signed by a trusted authority, issued for the host you entered, and not expired. A self-signed certificate fails that check.
Any host and port. Check a website on port 443, or put the port in the address, such as mail.example.com:465, for mail servers and other TLS services.
Expiry reminders on your terms. Get the reminder 30 days before expiration, at 14, or 24 hours out, or whenever the certificate fails verification. Each rule can change the monitor's status and open an incident.
Alerts on every channel. Alerts go out by email, SMS, phone call, Slack, Discord and browser push, the same channels every other monitor uses.

How it works

Create a monitor and choose SSL Certificate. Enter the host, such as example.com, or host:port for another service.
In the monitor's criteria, add a rule on Expires In Days, Less Than, 30, and turn on Change Monitor Status and Create Incident.
Add a second rule on Is Not A Valid Certificate, so a broken chain or a wrong hostname reaches you too.
Choose who hears about it: email, SMS, phone call, Slack, Discord and browser push.

What the Free plan includes

10 monitors: one per certificate you watch
Expiry, trust and hostname checks
Incidents, on-call and alerts
No credit card, and no time limit

Every plan and limit is on the pricing page.

Questions

What is SSL certificate monitoring?

SSL certificate monitoring is checking a site's TLS certificate on a schedule, so that an expiry, a broken chain or a certificate issued for the wrong host is caught before visitors see a browser warning. Uptimely does it with an SSL Certificate monitor: it connects to the host, reads the certificate, and checks the days left, whether it is trusted and whether it matches the host. The rules you add decide which of those findings alert your team.

Can Uptimely remind me before my SSL certificate expires?

Yes, once you add an expiry rule. Set Expires In Days to less than 30, or whatever lead time you want, and the monitor changes status when the certificate crosses that line and opens an incident once it has failed the monitor's failure threshold of consecutive checks (2 by default), with the reminder sent on the channels you chose. Without a rule, the monitor reads the days left but does not alert on them.

How do I monitor SSL certificate expiration?

Create an SSL Certificate monitor for the host, add a rule on Expires In Days, Less Than, 30, and turn on Change Monitor Status and Create Incident. Uptimely then tracks the days left on every check, and when the certificate crosses that line your team gets the expiry reminder on the channels you chose.

Can it check certificates on ports other than 443?

Yes. Put the port in the address, for example mail.example.com:465 or example.com:8443. Without one, the monitor uses the port you configured on it, and 443 if you set none.

Does it catch self-signed or misconfigured certificates?

Yes, once you add a rule for it. Every check verifies the certificate chain, the expiry date and the hostname you entered, and a rule on Is Not A Valid Certificate alerts you when any of them fails: a self-signed certificate, an expired one, one issued for another host, or one from an untrusted chain.

Does Uptimely renew certificates?

No, it watches them. Renewal stays with whatever issues your certificates today, such as your host, your load balancer or a tool like certbot, and Uptimely tells you when that process has stopped working.

Watch your first certificate on the Free plan. No credit card needed.

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