Keyword & Content Monitoring
Verify your content is always what you expect.
A page that returns 200 OK can still serve the wrong content — a blank page, an error message beneath a header, a cached version of a deleted page, or defaced content. Keyword monitoring fetches your pages on a schedule and verifies that specific words, phrases, or identifiers are present (or absent) in the response, catching content regressions that HTTP status codes would never surface.
HTTP 200 doesn't mean the page is correct
Many of the most damaging content failures are completely invisible to uptime monitoring. A CDN caching an error page returns 200. A CMS that crashes mid-render serves a blank body with 200. A page after a botched deployment loads the header and footer but renders empty content between them — all returning 200 with no indication of a problem unless you're looking at the content itself.
Defacement is the more adversarial version of the same blind spot. An attacker who compromises a CMS or an edge cache doesn't need to break your server to do damage — a page that returns 200 with someone else's message on it is a real incident that a status code check will never flag, because from the server's perspective nothing went wrong at all.
Keyword monitoring provides a layer of content validation that uptime monitoring cannot. By checking that a specific term — a product name, a critical sentence, a page element — is present on every check, you catch these invisible failures immediately rather than when a customer reports seeing the wrong content.
What NetTests keyword monitoring checks
NetTests fetches each monitored page on a schedule and searches the response body for the terms you configure. A check can require a term to be present — your product name, a price, a piece of critical copy — or require a term to be absent, such as "error," "exception," or the text of a known failure page. Either check runs against the actual HTML returned, the same content a real visitor's browser would receive.
Beyond exact keyword checks, NetTests can compare page content against a saved baseline and flag a significant change — useful for catching defacement or an unauthorized edit on a page that isn't expected to change often, where any difference at all is worth a look.
Check frequency is configurable per page, from every minute for content that changes rarely and needs to stay exactly right, to a longer interval for pages where you're mainly watching for the page to still exist and render at all. Alerts reach your team through email, Slack, Microsoft Teams, or SMS the moment a check fails.
Key features
Keyword presence checks
Alert when an expected keyword or phrase is absent from the page response body.
Keyword absence checks
Alert when a term appears that shouldn't — such as "error," "exception," or a known failure message.
Content change detection
Alert when the content of a page changes significantly from the baseline — useful for detecting defacement or unauthorized edits.
Scheduled checks
Fetch and validate page content on any interval — from every minute to daily — based on how frequently the content changes.
Real response body checks
Checks run against the actual HTML returned to a visitor, not a cached assumption of what the page contains.
Multiple terms per check
Require several terms present, absent, or both on the same page in a single monitor.
Full check history
Every run logged, so you can see exactly when content changed and what the page looked like at each check.
Multi-channel alerts
Reach your team through email, Slack, Microsoft Teams, or SMS the moment a check fails.
What you'll see
A live look at content checks across your monitored pages, and the alert that fires when an expected term goes missing.
Not ready to commit?
Try the free HTTP Request Timing tool first. Fetch a page right now and see exactly what's in the response, then set up continuous monitoring to catch the moment that changes.
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Frequently asked questions
How is this different from uptime monitoring?
Uptime monitoring checks that a page responds with a healthy status code. Keyword monitoring checks what's actually in the response body. A page can return a perfect 200 while showing a blank screen, a cached error page, or someone else's content entirely — all things uptime monitoring alone would never catch.
Can I check for multiple keywords on the same page?
Yes — a single monitor can require several terms to be present, several to be absent, or a mix of both. Useful for pages where more than one piece of content matters, like confirming both a product name and an "Add to cart" button are present on a product page.
What's a good use case for absence checks specifically?
Catching error conditions that still return a 200 status — a caught exception rendered into the page instead of a proper error page, a "database connection failed" message shown inline, or leftover debug output that shouldn't be visible in production. None of these change the HTTP status code, so an absence check is often the only thing that catches them.
Does content change detection produce a lot of false positives on pages that update often?
It can, which is why change detection is best suited to pages that are expected to stay stable — a terms-of-service page, a pricing page, a static marketing page — rather than a blog index or anything with frequently rotating content. For pages that change often, an explicit keyword check for the specific thing you care about is usually the better fit.
Can this catch a defaced page after a security compromise?
Yes, in two ways: an absence check on your own expected content (your brand name, a known page element) will fail if it's been replaced, and content-change detection flags the page as significantly different from its baseline. Neither is a substitute for actual security monitoring, but both catch a defacement fast — often faster than a person noticing.
Validate your content automatically
NetTests fetches your pages on a schedule and verifies that the right content is present — catching blank pages, caching errors, and content regressions that status codes miss.
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