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Preview of Site Spy

Site Spy by Vitaly Kuprin

Track and monitor website changes with this web extension

5 (1 review)5 (1 review)
6 Users6 Users
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About this extension
Site Spy — Track Website Changes Automatically

Know the moment any webpage changes. Site Spy monitors the sites you care about and shows you exactly what was added or removed — with visual diffs.

Use the extension or the web dashboard — your choice. Manage watches from the browser toolbar, or from the full dashboard on any device.

Documentation & Guides

Features
- Visual Diff Viewer — Side-by-side comparisons highlight every addition and removal
- Automatic Monitoring — Set custom recheck intervals. Get browser notifications when content updates
- Web Dashboard — Full dashboard at sitespy.app for managing watches, viewing diffs, and configuring notifications — works on any browser including mobile
- Snapshot Timeline — Browse the complete change history of any tracked page. Compare any two versions
- Full-Page & Element Tracking — Monitor an entire page or target a specific CSS selector for precision tracking
- Smart Tags — Organize tracked sites with color-coded tags. Filter and find what matters fast
- Dark & Light Themes — Clean interface that adapts to your preference

Two Ways to Track
- Track Current Page — One click adds whatever page you're viewing
- Track Any URL — Enter any public website URL to start monitoring

Great For
- Price and stock monitoring
- Competitor website tracking
- Documentation and changelog updates
- News, blogs, and job postings
- Any public webpage you want to keep an eye on

How It Works
1. Click the Site Spy icon in your toolbar
2. Track the page you're on or enter any URL
3. Get notified when something changes
4. View exactly what changed with visual diffs

🌐 sitespy.app | 📖 docs.sitespy.app

Track smarter. Stay informed.
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Permissions and data

Required permissions:

  • Display notifications to you
  • Access browser tabs

Optional permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
Learn more
More information
Add-on Links
  • Homepage
  • Support site
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Version
1.0.62
Size
12.69 MB
Last updated
3 days ago (Mar 12, 2026)
Related Categories
  • Web Development
  • Privacy & Security
  • Alerts & Updates
License
All Rights Reserved
Privacy Policy
Read the privacy policy for this add-on
Version History
  • See all versions
Tags
  • content blocker
  • dark mode
  • download
  • google
  • privacy
  • search
  • security
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