SSL certificate monitoring

Never miss an expiry

Track SSL certificates across all your client sites. Get alerted weeks before they expire so you never face a browser security warning.

clientsite.com

Status

valid

Issuer

Let's Encrypt

Valid from

Jan 10, 2026

Valid until

Apr 10, 2026

31 days

shop.acmeco.com

Status

valid

Issuer

Cloudflare, Inc.

Valid from

Feb 1, 2026

Valid until

Mar 18, 2026

8 days

Why SSL monitoring

Expired certificates destroy client trust

An expired SSL certificate triggers browser security warnings that scare visitors away, tanks your client's SEO rankings, and breaks any API integrations relying on HTTPS. For agencies managing dozens of sites, a single missed renewal can mean lost revenue and a difficult client conversation.

  • Automatic scanning of all SSL certificates
  • Configurable alert thresholds (7, 14, 30, 60, 90 days)
  • Certificate chain and issuer tracking

Certificate check · clientsite.com

Issuer
Let's Encrypt
Valid from
Jan 10, 2026
Valid until
Apr 10, 2026
Alert thresholds
7 · 14 · 30 · 60 · 90 days
On expiry
Open incident + alert

Features

Complete SSL visibility

Expiry alerts

Get notified 7, 14, 30, 60, or 90 days before a certificate expires. Customize thresholds per monitor.

Certificate details

See the full certificate chain, issuer, valid dates, and certificate type for every monitored domain.

Multi-domain coverage

Monitor SSL across all your client sites in one place. No per-certificate fees: it's included with every monitor.

Instant notifications

Email, SMS, Slack, and webhook alerts ensure the right person knows about expiring certificates immediately.

Incident tracking

When a certificate expires or changes unexpectedly, an incident is automatically created with full diagnostics.

Bundled with uptime

SSL monitoring runs alongside your uptime checks. No extra configuration: just enable it when creating a monitor.

Coverage

Every certificate, checked continuously

SSL monitoring runs alongside your uptime checks on every monitor, with no per-certificate fees. Set the alert window you want and Sentinel keeps watching the chain, the issuer and the expiry date for you.

30d

Default alert window

24/7

Continuous scanning

100%

Certificate coverage

0

Missed expirations

FAQ

SSL monitoring questions.

Still have questions? Get in touch.

How far in advance does Sentinel warn me about SSL expiry?

Sentinel alerts you weeks before a certificate expires, giving you plenty of time to renew before visitors ever see a browser security warning.

How will I be notified about an expiring certificate?

Alerts can reach you by email, SMS, Slack, Discord, and webhooks. Route them to whichever channel your team watches most closely.

Can I monitor SSL certificates for all my client sites at once?

Yes. Sentinel is built for agencies and freelancers, so you can track SSL certificates across every client site from a single account.

Does SSL monitoring replace uptime monitoring?

No, they complement each other. SSL monitoring is one of several monitor types and sub-checks alongside HTTP uptime, DNS, domain expiration, keyword, JSON/API response assertions, ICMP ping, TCP port reachability and heartbeat/cron job monitoring.

What happens if a certificate expires unexpectedly?

Sentinel keeps checking your certificates continuously, so if one expires or changes you are alerted right away rather than finding out from a client.

Is there a free trial for SSL monitoring?

Yes. Paid plans come with a 14-day free trial, there is also a free plan, and you can cancel anytime.

Never let a client's SSL certificate expire

Start monitoring SSL certificates across all your client sites.

No card for the free plan · 14-day trial on paid plans · Cancel anytime