Wachete - Track web page changes and get notified. Free Sign-up. Have all data in one place
Monitoro - Monitor webpages and get fresh data sent to your webhooks.
WebSite-Watcher - WebSite-Watcher detects website updates and highlights all changes in the text. WebSite-Watcher monitors web pages, password protected pages, disucssion forums and much more.
Accordably - Competitor monitoring made easy.
Visualping - Visualping is the easiest to use website checker, webpage change monitoring, website change detector and website change alert software of the web. Read more about Visualping.
GitHub Diff - Compare changes across GitHub branches, commits, or tags