Performance & content
Core Web Vitals, CDN, compression, CMS, sitemap, WebSocket, time-sync and file transfer.
Beyond "is it up?", these monitors check that your site is fast, correctly delivered, and that supporting services behave.
Core Web Vitals (browser)
Loads your page in a real browser and measures Google's Core Web Vitals along with a Lighthouse-style performance score.
- Metrics: LCP, CLS, INP and more.
- Device profile: test as desktop or mobile.
- Performance score shown in the monitor list at a glance.
- Presets: score regression, a specific metric over threshold.
There's also a free Core Web Vitals checker for one-off tests without creating a monitor.
CDN
Detects which CDN / edge provider is serving your site and alerts if it changes — with a Provider must be rule that expects a specific provider.
Brotli (compression)
Checks whether responses are served with Brotli compression and the expected encoding — smaller payloads, faster loads.
Favicon
Confirms your favicon loads, with a preview and status — a small but visible sign of a healthy site.
CMS
Detects the CMS / platform behind a site and can assert an expected match — useful for catching unexpected platform changes.
Sitemap
Validates your sitemap.xml — that it's present, well-formed and reachable
— so search engines keep crawling you.
WebSocket
Checks a WebSocket endpoint: handshake, ping/pong liveness, and optional pattern match on messages.
NTP
Checks a time server's sync status and quality (offset, samples) — important wherever clock drift breaks signing, tokens or logs.
FTP / SFTP
Checks file-transfer servers: connection, stage timings, and optional directory listing, write test and throughput test.
For FTP/SFTP, the listing, write and throughput operations are driven by alert rules rather than buried in settings — turn on exactly the checks you care about.