Monitor
SSL expiry monitor that emails you before customers see the warning.
Most certificate renewals fail silently. The host thinks it renewed; the cert path says otherwise. SiteGuardian probes the cert path daily and tells you the exact day, with a 90 / 30 / 7 / 1-day out cadence.
- Daily certificate path check. The same probe a browser would run.
- Alerts at 90, 30, 7, and 1 day before expiry.
- Free on every plan. Starter, Pro, Lifetime all ship it.
- Works with Let’s Encrypt, DigiCert, Sectigo, and any other CA in the chain.
- No agent on your server. SiteGuardian watches the cert from the outside.
How it works
Setup, in three beats.
Step 01
Add the URL behind the cert you want watched
Paste https://example.com (the URL a visitor types). SiteGuardian opens the connection, reads the certificate, and stores the expiry date. The next probe starts inside the next minute.
Step 02
Sit on the daily cadence
SiteGuardian re-checks every day. It does not spam you unless an expiry threshold fires. The 90 / 30 / 7 / 1 cadence means you learn about a problem weeks before a customer does.
Step 03
Renew or migrate before the warning hits the browser
A renew failure by your host or registrar is the most common silent breakage. By the time the warning bar shows up at the top of a visitor’s browser, you have already had a 90-day warning in your email.
What the alert actually says
One email. One URL. One timestamp.
Your certificate for https://example.com expires on 2026-09-14. 30 days from today. The renewal path appears to be failing; renew now or migrate before the browser warning page renders.Frequently asked
The ssl expiry monitor questions, answered flat.
Frequently asked
Try it
Start monitoring my site.
Starter is $19 a month — one site, ten URLs, every-five-minute checks. Pro is $39 a month — three sites, fifty URLs, every-minute checks. Lifetime is $299 paid once and stays yours with every future update included.
Stay updated
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