How to monitor a website for changes

Whether it's a restock, a price cut, a new SEC filing, or a competitor quietly rewriting their pricing page — the problem is the same: a page you care about will change, and you want to know the moment it does. Here's every realistic way to do that, from free-and-manual to fully automated, with the tradeoffs stated plainly.

Method 1 — Check it yourself (free, and why it fails)

Bookmark the page, open it every morning. Free, zero setup, and it fails for the exact reason you're reading this: the change never happens on your schedule. A restock that sells out in nine minutes doesn't care that you check at 9am. Manual checking works only when "sometime this week" is precise enough.

Method 2 — Browser extensions

Extensions like Distill's free tier or PageProbe watch pages while your browser is open. That's the catch — close the laptop and monitoring stops. They're genuinely good for same-day watching ("tell me when this queue page moves") and wrong for anything that can happen overnight.

Method 3 — RSS, if the site offers it

If the site publishes a feed (news sites, blogs, government agencies often do), an RSS reader is clean and reliable — but a reader still only tells you when you open it. The upgrade is piping the feed into an alerting tool so a new item becomes a push notification. (TrackerHub does this natively: paste a feed URL and new items alert in seconds.)

Method 4 — Self-hosted tools

changedetection.io and urlwatch are the standouts: free, open source, and powerful if you're happy running Docker on a VPS and maintaining it. The hidden costs are the server, the updates, and the silent-failure problem — a monitoring stack that's down doesn't tell you it's down. We wrote an honest breakdown of that tradeoff in our changedetection.io comparison.

Method 5 — Hosted monitoring services

Hosted tools (TrackerHub, Visualping, Distill's cloud tier, ChangeTower) run the checks on their own infrastructure around the clock. What separates them in practice:

• Check frequency. Free tiers typically check hourly or daily — fine for "did the docs change," useless for restocks. TrackerHub checks most pages every 1–2 seconds on every plan.
• Where the alert lands. Email is the default everywhere, but email is where urgency goes to die. Look for real push notifications to iPhone and Windows, or Slack/Discord/Telegram delivery, so the alert physically buzzes you.
• False positives. A tool that compares raw bytes will treat a rotating timestamp or a swapped ad slot as a change and spam you. What separates a tool you trust from one you mute is whether it reads the page's text and lets you say which words matter, so an alert means the thing you care about moved. Ask, or trial it.
• Social media. Logged-out scraping of X/Twitter breaks constantly because bot walls serve an empty shell. Proper coverage needs the official APIs (TrackerHub receives X posts by streaming push) or a real headless browser for Instagram/TikTok.

The comparison at a glance

Picking by what you're watching

• Restocks & price drops: you need second-level checks and a push alert — this is the least forgiving category. Hosted, fast-cadence only.
• SEC filings / official announcements: feed- or filing-driven, so speed of delivery matters more than crawl cadence. RSS-native tools shine here.
• A person or brand posting: skip the scrapers; use something wired into the platform APIs.
• Docs, ToS, competitor pages: anything works; pick whatever you'll actually keep running. The tool you maintain least wins.