FollowThatPage vs changedetection.io is a comparison between two very different philosophies. Follow That Page is a small hosted service run as a hobby: paste a URL, get an email diff. changedetection.io is an open source project you can run on your own box, with selectors, browser automation and a long list of notification targets. Developers who outgrow the first often reach for the second. This piece compares them on the things a developer cares about, then adds a third option, AyeWatch, for when you want a hosted API and would rather not maintain selectors.
At a glance
| Follow That Page | changedetection.io | AyeWatch | |
|---|---|---|---|
| Where it runs | Its own server | Your server, or hosted | Hosted |
| Price | Free account, paid Pro via PayPal | Free self-hosted, $8.99/mo hosted | Free Preview, then $9 to $99/mo |
| JavaScript pages | Not executed | Real Chrome browser available | Not stated |
| Logins | Never supported | Browser steps | Public pages |
| Targeting | Line and block keyword filters | CSS, XPath | Plain-English rule |
| Alerts | Email only | 85+ notification channels | Push, feed; email, Slack, Discord, webhooks on paid plans |
| API | None listed | Yes | REST API, signed webhooks, MCP server on paid plans |
How each one decides something changed
Follow That Page fetches the page as HTML, converts it to plain text and compares it with the last copy. You trim noise with two filters. A line filter drops lines containing a keyword, or keeps only lines that contain one. A block filter keeps or ignores text between two markers. It is simple and predictable, and it is also blind to anything a script renders, because the robot does not execute JavaScript at all.
changedetection.io lets you point at exactly the part of the page you want with CSS or XPath, and the hosted plan includes a real Chrome browser for pages that need one. Browser steps let it log in or click through before it reads the page. Precision is the selling point. The cost is that selectors are tied to page structure, so a redesign can break them.
AyeWatch skips selectors. You write a sentence, such as "alert me when a new major version appears in the release notes, ignore patch releases", and it judges each change against that. It sends a short summary rather than a diff. That makes it resilient to layout changes, at the cost of element-level precision.
Check frequency and limits
Follow That Page is quota-based. Free accounts get 20 daily checks and one hourly check per user; Pro accounts get 1,000 daily, 20 hourly, five 10-minute and 100 weekly checks. Pages over the quota wait in a queue. The fastest interval is 10 minutes, a limit the author set to avoid hammering small sites.
changedetection.io on your own hardware is limited by your hardware. The hosted plan includes 5,000 URL watches for $8.99 a month.
AyeWatch has no queue to manage. Each monitor sets its own pace, with Auto mode speeding up while a page is changing, and paid plans start at $9 a month.
Integration surface
This is where Follow That Page drops out. It sends plain text email and that is the whole interface.
changedetection.io has its own API and pushes to dozens of services, which makes it easy to fan alerts into chat, a pager or a script.
AyeWatch's API is included on every paid plan. You can create, list, update and delete topics programmatically and receive signed topic.update webhook events with the AI summary attached. There is also an MCP server at https://ayewatch.ai/api/mcp, so an AI coding assistant can create or pause monitors directly. Alerts can also go to Slack or Discord without any glue code.
Maintenance
Follow That Page needs none from you, but its FAQ is frank that one developer runs it in his spare time, that fixes can take a while, and that it had a long outage in May 2023 after a hardware failure. Status updates go out on Bluesky.
Self-hosted changedetection.io needs what any service needs: updates, backups, monitoring of the monitor. The hosted plan removes most of that.
AyeWatch is hosted, with no contracts, and you can cancel any time.
Which to pick
- changedetection.io if you need logins, click-through flows, exact selectors or self-hosting. It is the better tool for those jobs.
- Follow That Page if you want zero setup for a plain HTML page and email is enough.
- AyeWatch if you want a hosted service with an API, webhooks and push alerts, and you would rather describe a change in English than keep selectors in sync with someone else's markup. It also watches topics and social accounts, which the other two do not.
The AyeWatch Free Preview includes three monitoring runs, no card required, which is enough to test a rule against a real changelog. The full comparison of FollowThatPage alternatives covers a few more tools.