Monitoring

Understand how PageDrifter detects changes and configure monitoring to suit your needs.

How Change Detection Works

PageDrifter regularly visits your monitored URLs and compares the current content with the previous snapshot. When differences are detected, you receive a notification.

The Detection Process

PageDrifter visits your URL at the scheduled interval
The page content is captured based on your monitor type
Content is compared against the previous snapshot
If changes exceed your threshold, you're notified
The new snapshot becomes the baseline for future checks

Monitor Types

Choose the detection method that best fits your monitoring needs:

Text Content

Extracts and monitors visible text content from the page. This is the most common choice and works well for:

Blog posts and articles
Pricing pages
Product descriptions
Documentation pages

Visual (Screenshot)

Captures a screenshot and compares visual differences. Ideal for:

Design-heavy pages
Pages with charts or graphs
Image-based content
Layout changes

Visual monitoring uses more resources and counts as 2 checks per run.

HTML Source

Monitors raw HTML for any changes, including invisible elements. Best for:

Meta tag changes
Script updates
Technical monitoring
SEO auditing

Using CSS Selectors

Focus monitoring on specific parts of a page using CSS selectors. This reduces noise and helps you track exactly what matters.

Common Selectors

Selector	Matches
#price	Element with id="price"
.product-info	Elements with class="product-info"
article	All article elements
[data-testid="stock"]	Element with data-testid="stock"
main .content	.content inside main

Tip: Use your browser's developer tools (right-click → Inspect) to find the right selector for the content you want to monitor.

Check Frequency

How often PageDrifter checks your URLs depends on your plan:

Plan	Minimum Interval
Free	Daily
Starter	Hourly
Pro	5 minutes
Business	1 minute

Change Threshold

Set a minimum change percentage to filter out minor fluctuations:

0%: Alert on any change (most sensitive)
5%: Ignore minor text changes
10-20%: Only alert on significant changes

The percentage represents how much of the monitored content changed compared to the previous snapshot.

JavaScript Rendering

Some websites load content dynamically using JavaScript. For these pages, enable JavaScript rendering in your monitor settings.

JavaScript rendering is available on Pro and Business plans. Each check with JS rendering counts as 3 standard checks.

When to use JavaScript rendering:

Single-page applications (React, Vue, Angular)
Pages with lazy-loaded content
Content loaded via AJAX calls
Interactive dashboards and portals

Best Practices

Use specific selectors

Instead of monitoring entire pages, target specific sections to reduce false positives from ads, timestamps, or dynamic content.

Match frequency to importance

Critical monitors deserve frequent checks, but less urgent monitoring can run daily to conserve your check quota.

Set appropriate thresholds

If a page has dynamic elements you can't exclude, use a higher change threshold to filter out noise.

Name monitors descriptively

Use names like "Competitor X - Pricing Page" instead of just the URL for easy identification in notifications.