Update Scanner
Open Source
Update Scanner is a Firefox addon to monitor web pages for updates. Useful for websites that don't provide Atom or RSS feeds.
WebSite-Watcher
Commercial
WebSite-Watcher detects website updates and highlights all changes in the text.
Wachete
Freemium
Wachete is a website content monitoring platform.
ChangeMon.Com
Free
ChangeMon.Com is an online website change monitor service.
Compare ChangeDetect with alternatives
Compare Update Scanner and ChangeDetect and decide which is most suitable for you.
Compare Wachete and ChangeDetect and decide which is most suitable for you.
Compare WebSite-Watcher and ChangeDetect and decide which is most suitable for you.
Compare ChangeMon.Com and ChangeDetect and decide which is most suitable for you.