Site Spy: Monitor webpage changes and get notified via RSS feeds.

What it does

Site Spy monitors webpages for changes and alerts users when specific content has been updated. Instead of tracking an entire page, users select a particular element—a price, appointment slot, stock status, or headline—and the tool checks for changes on a schedule they set. When something changes, users see a visual diff, browse snapshot history, or receive updates through an RSS feed.

Who it is for

The tool serves people who need to track specific information on websites but do not want constant noise from unrelated page updates. Use cases mentioned include monitoring prices, appointment availability, product restocks, competitor activity, and new listings. The founder's original motivation was tracking visa appointment slots on government websites.

Pricing

The site offers a free plan with monitoring for two pages and no credit card required. Multiple notification channels are included across all plans: email, Telegram, browser push notifications, and webhooks. Extension versions are available for Chrome and Firefox.

How it stands out

Site Spy differs from competitors by allowing granular selection of page elements rather than whole-page monitoring. Users click or draw a box around the exact content they want to track. The tool displays changes as visual diffs showing exactly what was added or removed, and supplies a full history of snapshots for comparison. The RSS feed integration allows monitoring through third-party readers instead of relying solely on email or push notifications. Browser extensions enable one-click setup directly from the toolbar.

What a founder should check

First, identify how Visualping and Distill—mentioned as alternatives on the homepage—have addressed the same problem and what barriers prevent their users from switching. Second, verify whether the free tier's two-page limit creates sufficient friction to drive conversion or whether users simply abandon the tool rather than upgrade. Third, assess the switching costs for users who have already configured watches in competing services and examine whether Site Spy makes migration painless enough to overcome that inertia.

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