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. Naive tools hash the whole page, so a rotating timestamp or ad triggers "it changed!" spam. Good ones extract the meaningful content first. Ask, or trial it — this is the difference between a tool you trust and one you mute.
• 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.