Advanced Website Monitoring
Check what a page or API actually returns — including authenticated endpoints.
Advanced Website Monitoring adds assertions and request control to every HTTP/HTTPS check: regex and forbidden-keyword checks on the body, assertions on response headers and on values inside a JSON body, and custom request headers and bodies. Use it to catch an error banner on a page that still returns 200, to require a field in an API's JSON answer, or to probe an authenticated API with a token or a payload. When a check fails, a diagnostic check shows which assertion broke and what the service answered.
What it detects
- Content that doesn't match a regular expression you define
- A forbidden string or pattern appearing — an error banner, a maintenance page, a stack trace
- A response header that is missing or wrong — a Content-Type, a security header, a cache policy
- A JSON value that isn't what you expect — a status field, a number past a limit, an item missing from a list
- Authenticated API endpoints failing, using your own Authorization header or API key
- Endpoints that need a POST body or custom headers to answer correctly
How you're alerted
- A failed assertion fails the probe, so the automatically attached “HTTP Down” rule fires.
- A diagnostic check is captured the moment the monitor goes down: every assertion's result, the reason each probe location reported, and the first 2 KB of the response.
- Header and body values are stored encrypted and never returned by the API; the dashboard shows header names only.
Notifications go to any of 8 channels — see notifications.
- Runs from
- Every probe region you assign — down only when all of them agree
- Adds to HTTP/HTTPS
- Regex assertions, forbidden keyword, response header assertions, JSON body assertions, custom headers and body
- JSON assertions
- A path such as data.items[0].status or items[*].status, with equals, not equals, contains, exists, greater than, less than
- Dashboard
- Failure reasons, failures over time, response size trend, which assertion failed and how often, diagnostic check history
- Included in every HTTP check
- Expected status codes, required keyword, Basic Auth, request method
- Available on
- Professional · Enterprise and Custom on request
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Start monitoring everything in minutes
Create a free account, add your first check and get alerted the moment something breaks — no credit card required.