Monitors · Pro

Watch any tool. Get pinged when it changes.

Schedule any host.tools probe to run every 1, 5, 15 or 60 minutes. Diff against the last run. Webhook + email + Slack alerts when something moves.

SSL expiry watch

Daily check on every cert. Alert at 30 / 14 / 7 / 1 day.

Domain expiry watch

Heads-up 90 / 30 / 7 days before WHOIS expiry.

DNS drift

Alerts the moment any record (A/AAAA/MX/TXT/NS) changes.

Multi-region uptime

Probes from 12 regions every minute. Alerts on partial outages.

Security-headers

Alert if your grade drops or HSTS preload status changes.

Blacklist watch

16+ RBLs scanned hourly — fire the moment you appear.

DMARC reports

Aggregate DMARC RUA reports parsed and visualised.

Custom probe

Pick any tool, any interval, any expected output.

Schedule a monitor

Tool

ssl/cert

Target

host.com

Interval

every 6 hours

Alert when

data.days_left < 30 OR data.expired = true

Notify

webhook + email + slack

Upgrade to Pro

Sample alert

{
  "event":     "monitor.alert",
  "monitor":   "ssl/cert host.com",
  "interval":  "6h",
  "fired_at":  "2026-05-09T04:10:56+00:00",
  "previous":  { "days_left": 14, "expired": false },
  "current":   { "days_left":  7, "expired": false },
  "diff":      { "days_left": -7 },
  "rule":      "data.days_left < 30",
  "severity":  "warning"
}