Page Change Detector
Get an email when a web page changes, with only the text that changed
Preview a page
See the text we would watch, before you make an account.
Want this checked for you? Watch this page and get an email when the text changes.
How a website change monitor works
- Add the page and say what to readPaste a public page address, then watch the whole page or one part of it with a CSS selector. The preview tool above shows the exact text that would be watched, and it needs no account.
- Pick how often to check, and what counts as a changeThe interval menu is 10 minutes, 15 minutes, 30 minutes, 1 hour, 6 hours or 24 hours, up to the fastest interval your plan allows. Any change is the default trigger. A monitor can also be set to alert only when a phrase appears, or only when it disappears.
- Get the diff by emailWhen the text moves, the email carries the summary and the changed lines, with added lines marked + and removed lines marked -. The dashboard keeps the same diff side by side with the full history, and every alert has a one-click pause link and a stop-alerts link.
Monitor website for changes, not noise
Most page alerts are not changes. A clock in a sidebar, a line reading 3 minutes ago, a session id that is different on every load, a cookie banner that reappears on every visit: alert on any of those and the email stops being worth reading.
Before two versions are compared, the text is normalized. Clock times, dates, relative times such as 3 minutes ago, long random-looking values that are really a session id or a CSRF token, and the usual cookie banner lines are removed. Runs of whitespace are collapsed and empty lines are dropped. What is left is hashed, and an alert goes out only when that hash moves, so an email means the readable text really changed.
Two more things keep the alerts honest. A page that cannot be reached is not a change: after 3 failed checks in a row one notice is sent, and no diff is invented. A page that answers with a bot wall is reported as blocked, not as changed. And when a selector stops matching, the last good text stays as the baseline instead of being replaced by an empty page.
What v1 does not do
Stated plainly, so nobody signs up expecting the wrong tool.
- Pages behind a login. Public pages only: no stored cookies, no signing in, no CAPTCHA solving, no working around a bot wall.
- Page actions. It does not click, scroll, fill in a form or wait for a button before reading.
- Screenshots. The comparison is text, so a moved image or a changed layout is not reported as a change.
- Price-drop parsing and AI summaries. The alert is the diff, and nothing is rewritten for you.
- SMS and Slack. Alerts are email only, to the verified address on the account.
- Social profile hosts. facebook, instagram, x, tiktok, linkedin, threads, snapchat, pinterest and reddit user pages are refused in v1.
Plans
One flat monthly price, and checks are never counted, so every monitor runs at its interval all month. The numbers below are read from the same plan configuration the server enforces.
Free
$0
Useful on its own, no card required.
- 3 monitors
- Every 60 minutes at the fastest
- 30 days of change history
Pro
$9 a month
For one person keeping an eye on a handful of pages.
- 25 monitors
- Every 15 minutes at the fastest
- 180 days of change history
- Browser rendering on up to 5 monitors
- REST API access
Business
$19 a month
For a team watching a lot of pages.
- 100 monitors
- Every 10 minutes at the fastest
- 365 days of change history
- Browser rendering on up to 20 monitors
- REST API access
Compare the plans and the price per page, or create a free account and add your first monitor. The free plan needs no card.
Frequently asked questions
Is it free?
The free plan watches 3 monitors, checked every 60 minutes at the fastest, with 30 days of change history and email alerts. The preview tool above needs no account at all. There is no trial period on the paid plans, because the free plan is the trial, and it needs no card.
How often are pages checked?
The interval menu is 10 minutes, 15 minutes, 30 minutes, 1 hour, 6 hours or 24 hours. Each plan has a fastest allowed interval: 60 minutes on Free, 15 minutes on Pro, 10 minutes on Business. A monitor that uses browser rendering runs every 30 minutes at the fastest on any plan. Checks are spread out with jitter inside the interval, so a set of monitors added in one sitting does not all fire together.
Can I watch the whole page, or just one part of it?
Both. Whole page mode reads the main text of the page and ignores the navigation, the footer and the scripts. Selector mode reads one element, which is how you watch a price, a stock line or a single table. The preview tool above lets you test a selector before you make an account. If the element you watch stops matching, the monitor reports that the selector was not found and keeps the last text it read, rather than reporting an empty page.
Does it work on pages built by JavaScript?
Sometimes. The basic check reads the HTML the server sends, with no browser involved. A page that builds its content in the browser can come back with almost no text, and the monitor says so instead of pretending. For those pages, browser rendering is available on Pro (up to 5 monitors) and Business (up to 20 monitors), every 30 minutes at the fastest. Rendering costs more to run, so it is capped per plan and off by default.
What counts as a change?
A change is the readable text moving once the noise has been stripped: something added, something removed, or both. Each monitor can be set to alert on any change, on a phrase appearing, or on a phrase disappearing. An image moving, a colour change or a layout shift is not a change here, because the comparison is text, not pixels.
What do you store, and who can see it?
The normalized text of each version and a hash of it, never the full HTML of the page. Change history belongs to the account that watches the page and is never public. History is kept for the plan's own window: 30 days on Free, 180 days on Pro, 365 days on Business. Takedown requests go to [email protected].
How do I stop the emails?
Every alert carries a link that pauses that one monitor and a link that stops alert emails for the whole account, and neither one asks you to sign in. Any monitor can also be paused, edited or deleted from the dashboard. Alerts are capped as well: at most 12 alert emails per monitor per 24 hours and a daily cap per plan. A page the watcher cannot reach sends one notice after 3 failed checks in a row.
Can a site owner opt out of being watched?
Yes. This is a watcher, not a crawler: one public page, once per interval, per monitor. A robots.txt group that names PageChangeDetectorBot is obeyed, and a host that would rather not be watched at all can write to [email protected] and be added to the blocklist. The watcher never sends cookies, never logs in and never claims to be a browser.