Everything that can break a certificate. Watched.

Expiry is only one way HTTPS fails. We catch the others too.

Expiry reminders on your schedule

30, 14, 7, 3 and 1 day out by default. Want 60? Add it. Hate noise? Drop to two.

Instant breakage alerts

Expired. Hostname mismatch after a migration. Broken chain after a server rebuild. Host unreachable. You hear about each within one check, not one customer complaint.

Why it failed, in plain English

"Your certificate covers www.example.com but not example.com. Add the bare domain to your next renewal." Every alert explains the cause and the fix. No PKI degree needed.

Alerts that reach a human

Email for the record, Slack or Teams for the team. Send each site's alerts where they'll get read.

Know when a certificate changes

When a site starts serving a different certificate, you get a note with the old and new issuer and expiry. Expected after a renewal, worth a look when nobody renewed.

Domain expiry and Certificate Transparency

Once a day we look up each domain's registration expiry over RDAP and warn at 30, 14, 7 and 1 day. We also watch public Certificate Transparency logs through crt.sh and tell you when a new certificate is issued for your hostname.

Webhooks, PagerDuty and an API

Send alerts to PagerDuty (Events API v2) or to your own endpoint as signed JSON. Add and read monitors from scripts with the REST API.

Bring your team

Invite admins and view-only members by email: 3 seats on Starter, 10 on Pro. Bulk import hostnames from a paste or CSV, export the list as CSV, and opt in to a monthly summary email.

Zero install

We check from the public internet. No agents, no firewall changes, no private keys.

Free checker for quick looks

Check any domain in seconds before you even sign up.