SiteMonit

Website change monitoring that shows you exactly what changed — not just that something did. SiteMonit renders any page in a real browser, then delivers a before/after diff with a slider and a Diff Axis — a live map of every addition, deletion, and edit you can click to jump to. Text mode marks changes inline, word by word, like tracked changes in a document. Monitor competitor prices, restocks, job postings, ToS updates, and more. Alerts via email, Telegram, Slack, or webhook.

Free plan available, checks every 15 minutes.