CertWatch now monitors HTTP uptime — not just cert and domain expiry

CertWatch started as a single-purpose tool: email you before your SSL cert or domain expires. That's still the core. But I kept running into a version of this situation:

Cert is fine. Domain is fine. Site is returning 503 for the last 6 hours. No alert.

The cert and domain watchers are predictive — they catch problems before they're problems. HTTP uptime is reactive, but in the specific way that matters: the moment your server stops responding, not the moment a customer complains.

What changed

Every domain CertWatch monitors now gets a daily HTTP check:

Attempt GET https://{domain}/
Any 2xx or 3xx response = OK
Anything else (4xx, 5xx, connection refused, timeout) = down

If the site was previously up (or this is the first check) and the response is non-2xx/3xx, you get an immediate alert — same day, same email path as cert alerts.

Transition-based, not flood-based

The alert fires once when the status transitions from up to down. If your server stays down for three days, you don't get three alerts. You get one alert when it first fails, and then silence until it recovers. This keeps the alert actionable instead of noisy.

The same idempotency rule applies: if CertWatch has already alerted you about this domain being down today, it won't fire again until tomorrow (or until you resolve it and it goes down again).

Why HTTPS only

CertWatch is a TLS-focused product. If you're not serving HTTPS on your monitored domain, you have bigger problems than uptime monitoring. The HTTP check is intentionally simple — just "does this domain return a healthy response over TLS?" If you need port-level monitoring or custom paths, that's Pingdom's territory.

Alert channels

The http_down event flows through the same fan-out as every other CertWatch alert:

Email (all tiers)
Slack webhook (Pro)
Discord webhook (Pro)
Teams webhook (Pro)
PagerDuty (Pro)

The severity is critical — same as cert_invalid and no_resolve. If your site is down right now, that's a paging event.

What it doesn't replace

CertWatch is not Pingdom. It doesn't check every 60 seconds, it doesn't do multi-region probes, and it doesn't have a status page dashboard. What it does:

Tells you today when your site stops responding — not when your users tell you
Does it as part of the same daily scan that's already watching your cert and domain
Adds zero configuration — it's on by default for all monitored domains

If you're already using CertWatch for cert/domain alerts, you got this for free.

CertWatch monitors domain expiry, SSL cert expiry, chain validity, DNS health, and HTTP uptime. Free for 5 domains. Paid tiers from $5/mo.