Content Monitoring
Every scan compared
against the last.
Nothing slips through.
After every scan, SiteVitals compares your page against its previous state - body copy, title, H1, word count, and every external resource loaded. A weighted change index tells you not just that something shifted, but how significant that shift was. Small edits score low. A rewritten page, a swapped headline, or a new third-party script injected into your markup scores high.
Weighted Change Index
Quantifies exactly how much a page has changed between scans - not just if it changed, but how significantly.
Keyword drift detection
Tracks whether your pages are maintaining their semantic focus on the terms they are supposed to rank for.
Dependency fingerprinting
Maps every third-party script and alerts you the moment a new external resource appears on the page.
Structural change detection
Flags changes to heading architecture, title tags, and canonical structure - the signals search engines rely on most.
Not just a snapshot.
A comparison engine.
Most monitoring tools tell you a page exists and is reachable. Content Monitoring goes further - after every scan, it compares what the page is now against what it was before, across four weighted dimensions: body copy, title tag, H1, and word count.
Before analysis, navigation, headers, footers, and boilerplate are stripped out so only meaningful body copy is evaluated. This prevents routine template changes from generating noise, and ensures the score reflects genuine content shifts rather than sidebar updates.
"A typo fix and a complete page rewrite both count as changes. The difference is how much they score."
The result is a Change Index between 0 and 1 - a precise, reproducible measure of how different the current page is from the last scan. A score near zero means little has changed. A score approaching 1 means the page is substantially different. Every scan result is logged, so the index tells a story over time, not just point to point.
📄 Body copy - 55%
The largest weight in the index. Jaccard similarity measures semantic overlap for long text; Levenshtein distance handles shorter passages. Both are normalised to a 0–1 scale.
🏷️ Title tag - 20%
Title tags carry significant search weight. Even a small rewrite is scored proportionally against the previous version.
📰 H1 - 15%
The primary on-page heading. Structural changes here - including removal or tag demotion - are caught and scored.
🔢 Word count - 10%
Significant word count drift relative to the previous scan contributes to the index, catching large additions or deletions that similarity scoring alone might not surface.
What Content Monitoring Detects
Three categories of change that affect your site more than you think.
Content Monitoring scans three distinct areas of your pages - each covering a different category of change that uptime or security monitoring won't catch.
How the content monitoring
engine actually works.
Most website monitoring checks whether a page is reachable. Content Monitoring goes further - using computational methods that measure the meaning and structure of a page, not just its surface content.
Weighted Change Index
A composite score that quantifies how much a page has changed between scans. Rather than a binary “changed / not changed,” the index measures the degree of change - distinguishing between a typo fix and a significant rewrite.
Jaccard Similarity
Measures the semantic overlap between two versions of a page by comparing the sets of terms present in each. A high Jaccard similarity means the pages share most of the same vocabulary. A declining score indicates semantic drift.
Levenshtein Distance
Measures the physical edit distance between two text versions - the minimum number of character-level operations required. Combined with Jaccard, this gives a complete picture of both text and meaning change.
Intelligent Noise Reduction
Before analysis, the engine strips navigation, headers, footers, and boilerplate to focus exclusively on core body copy. This prevents routine template changes from generating false positives.
External Dependency Fingerprinting
Every external domain and resource loaded by your page is fingerprinted on each scan. When the next scan runs, the current dependency map is compared against the previous one - any new domain, added script, or removed resource is flagged immediately, before it has a chance to cause harm.
Scan History & Audit Trail
Every scan result is stored, giving you a complete chronological record of how a page has evolved. When something changes - rankings, traffic, a client query - you have timestamped scan data to pinpoint exactly when a page looked different, without relying on memory or manual notes.
Your competitors' public pages
are trackable too.
Change Intelligence monitors any public URL - which means it isn't limited to sites you own. Add a competitor's key pages alongside your own, and SiteVitals will alert you whenever their content, structure, or third-party dependencies shift. The same technology that protects your site from quiet degradation also tells you when the competitive landscape is quietly moving.
Keyword drift detection
When a competitor's page begins shifting its semantic focus toward a new set of terms, you'll see the drift before it shows up in rankings.
Messaging and copy changes
Headline rewrites, repositioned value propositions, revised CTAs - logged with timestamps so you know exactly when the change happened.
New third-party scripts
Third-party dependency fingerprinting flags when a competitor adds a new analytics tool, ad network, or external service to their pages.
Structural changes
Changes to H1s, page titles, and heading structure are logged separately - often the first visible sign of an SEO strategy shift.
"A competitor quietly repositioning their core service page is useful intelligence. Knowing it happened three weeks ago, with a timestamp, is a different quality of insight entirely."
SiteVitals only tracks publicly accessible pages. No authentication, no scraping behind login walls - the same information any visitor would see, monitored continuously so you don't have to check manually.
The monitoring that explains
what everything else can't.
Content Monitoring is available on SiteVitals paid plans from £15.17 per month. It is the feature that tends to earn its keep most clearly in retrospect - the first time a page quietly changes in a way that matters, and you have the scan data to prove exactly when it happened.
It also works best the longer it runs. Every scan is logged, so the history builds quietly in the background. The first time a page changes in a way that matters - a ranking drop, a client question, a traffic anomaly - you have a timestamped audit trail that tells you exactly when it happened and what shifted. That kind of retrospective clarity is only possible if monitoring was already running.
Starter plan and above
Things people often ask us.
If something is not covered here, we are genuinely happy to answer it. We are a small team and we actually respond.
How do you calculate the "Change Index"?
We use a combination of Jaccard Similarity and Levenshtein distance to quantify the physical and semantic difference between page versions.
Does this detect malicious script injections?
Yes. By fingerprinting every external dependency, we alert you the moment a new third-party resource is loaded on your page.
Can I ignore headers and footers?
Absolutely. Our engine strips out boilerplate content to focus specifically on core body copy changes.