General 5 min read

Website change monitoring vs broken-link monitoring

Change monitoring tells you a public page's text moved. Broken-link monitoring tells you a link that used to work now fails. They answer different questions.

Use change monitoring when you need to know that the words on a public URL changed, the URL went down, or its certificate is nearing expiry. Use broken-link monitoring when you need to know that a link on a site you own, which used to work, now returns 404 or 410. Most sites that care about both run both. Neither tool does the other one's job.

Change monitoring

You name a public URL. Something fetches it on a schedule and compares it with last time.

SignalWatch compares visible text and sends a unified diff when it changes. The same monitor alerts when the page goes down or recovers, and when the TLS certificate is inside 14 days (again at 3 days). You can limit the comparison with a CSS selector, an ignore regex, and a minimum change. Alerts go to email, Slack, Discord, or an HMAC-signed JSON webhook.

It is the right tool for a page you do not control, or a page you control but want watched from the outside: a competitor's pricing page, a vendor status page, your own docs, a policy. Setup notes are in how to get alerted when a web page changes and how to monitor a competitor's pricing page.

Free: 3 monitors, every 15 minutes, no card. You can check a URL before you create an account.

What it does not do: crawl your site, inventory every href, or stay quiet about links that were already broken. One URL in, one stream of changes out.

Broken-link monitoring

You verify a site you own. The tool crawls pages, records the links it finds, and remembers them.

Mortise makes the first crawl a silent baseline. Later crawls alert only after a link fails twice as 404 or 410. Links that were already broken stay quiet. That rule is the whole product, and it is explained in why broken-link checkers keep reporting the same broken links.

Free: 1 site, 200 pages per crawl, a manual check at most once a day, dashboard only, no card. Pro ($12/month or $79/year) adds more sites, more pages, a schedule, email, a webhook for new breaks, and CSV.

What it does not do: tell you that a sentence changed, that a host is down in the uptime sense, or that a certificate is due. A page can be rewritten and still return 200 for every link.

Side by side

  • Question. SignalWatch: did this page's text change, did it go down, is the certificate close to expiry? Mortise: did a link that previously worked newly break?
  • Target. SignalWatch: any public URL. Mortise: a site you can verify you own.
  • Memory. SignalWatch: the previous text of that URL. Mortise: a baseline of links, so known broken links do not alert.
  • Noise control. SignalWatch: selector, ignore regex, minimum change. Mortise: baseline, plus a link must fail twice.
  • Free plan. SignalWatch: 3 monitors, 15-minute checks, no card. Mortise: 1 site, 200 pages, manual daily check, no card.
  • Paid start. Both Pro plans are $12/month or $79/year. The limits above that price are different, and they are listed on each product site.

When one is enough

Choose SignalWatch if the thing you might miss is an edit on a specific page, downtime of that URL, or a certificate date. A freelancer watching three client homepages, or a founder watching two competitors' pricing pages, does not need a link crawler for that.

Choose Mortise if the thing you might miss is a href that used to resolve and now does not, especially after a redesign or a content import. A single pricing URL will not show you that the blog template is emitting a dead related-post link.

For a one-off punch list of broken links, page errors, redirects, SEO basics, and SSL — not continuous new-break alerts — use SiteCheck. That job versus Mortise is in website inspection vs new-break alerts.

When to use both

Use both when you are responsible for a site and you also depend on pages elsewhere.

  • Mortise on your site, after the migration baseline described in how to find newly broken links after a website migration.
  • SignalWatch on the few public URLs whose wording you would act on: your pricing page (so an accidental edit is visible), a key vendor's status or changelog, a competitor's pricing page.

They stay separate. Separate sites, separate accounts, separate prices. There is no bundle. You can start on one free plan and add the other later.

Together, that is a page check and a link check, without a suite that also wants to be your CMS.

A small way to decide this afternoon

  1. Write down the URLs you would be annoyed to see changed. If the list is one to three public pages, start with SignalWatch.
  2. Write down whether your own site has shipped a template, a migration, or a large edit lately. If yes, baseline it with Mortise.
  3. If both lists are real, use both. If only one is real, use that one.

The tools are listed together on the Litework tools page.