Link Checker: Read It and Fix It

A link checker crawls your website and reports every link that leads nowhere: internal links to missing pages, outbound links to sites that have gone dark, and redirect chains that waste time and crawl budget. Running one is easy. Knowing what each finding means and how to fix it is where the value lives. This guide explains what a link checker inspects, which free tools do the job well, and exactly how to resolve everything a scan turns up.

What a link checker does

When a link checker runs, it starts from a page you give it, reads every link on that page, follows each one, and records the HTTP status the server returns. It repeats this across your whole site, building a map of which links work and which do not. The key output is the status code behind every link. A 200 means the destination is healthy, a 301 or 302 means it redirects, and a 404 means the target is missing. As MDN's HTTP reference notes, links that lead to 404 pages are commonly called broken or dead links, and finding them is the checker's main job.

Most tools sort their findings so you can act quickly, grouping links by status and, crucially, telling you which of your pages contains each broken link. That "source page" column is what turns a raw error list into a fixable to-do list.

Internal, outbound, and redirected links

A good scan separates three kinds of problem, because each has a different fix.

• Broken internal links point from one of your pages to another page on your site that no longer exists. These are entirely your responsibility and the highest priority, because they trap visitors and waste crawl budget inside your own site.
• Broken outbound links point to other websites that have moved or shut down. You did not break them, but they still reflect on you, so they need updating or removing.
• Redirect chains and loops are links that pass through several hops before landing, or that loop endlessly. They slow pages down and dilute ranking signals.

Broken internal links are part of the wider problem of broken links and their SEO impact, and every 404 a checker finds connects back to the causes and cures in our guide to fixing 404 Not Found errors.

An honest note about free link checkers

404Pulse does not run a secret proprietary crawler, and you do not need one. Several genuinely free and respected tools cover this task well. The right choice depends on the size of your site and how deep you want to go.

• Screaming Frog SEO Spider (free tier). A desktop crawler that maps internal and outbound links and reports response codes. The free version crawls up to a set URL limit, which is plenty for small and medium sites.
• W3C Link Checker. A long-standing free web tool that checks the links on a page or site and reports broken ones, with no install required.
• Google Search Console. Its Pages report shows URLs Google encountered that return "Not found (404)," which reflects the broken links Google itself is following.
• Browser and CMS extensions. Lightweight crawl extensions and plugins are handy for spot checks on a single page or a small site.

How to read a link checker report

Once a crawl finishes, resist the urge to fix links at random. Work the report methodically.

1. Sort by status code. Group everything returning 404 and other 4xx or 5xx errors. Those are your genuine breakages.
2. Split internal from external. Internal errors come first, because you can fix both ends and they hurt the most.
3. Read the source column. For each broken link, note which of your pages it lives on. That is where you make the edit.
4. Flag redirect chains. Look for links that hop through multiple redirects and plan to point them straight at the final destination.
5. Ignore the noise. Some links return errors only for bots or require a login. Verify a sample manually before treating every flagged link as broken.

How to fix what a link checker finds

Each category of finding maps to a clear action.

Broken internal link, target still exists elsewhere. If the destination page simply moved, either update the link to the new URL or add a 301 redirect from the old URL to the new one. Editing the link at its source is cleanest when the broken link lives on your own pages, because it avoids an extra redirect hop.

Broken internal link, target is gone for good. Point the link to the most relevant live page, or remove it if no good replacement exists. Do not leave a link that leads to a dead end.

Broken outbound link. Find a current, authoritative replacement and swap it in. If the resource is gone entirely, remove the link or reference an alternative source so your content stays trustworthy.

Redirect chains. Update the link to point directly at the final URL so requests resolve in one hop. Where possible, use a permanent 301 for genuinely permanent moves, which Google recommends in its guidance on redirects and Google Search, so ranking signals transfer cleanly. To confirm your fixes return the codes you intended, a redirect checker verifies each URL's response.

Make link checking a routine

Links break continuously as you edit pages, run campaigns, and link out to sources that later disappear. A single scan is a snapshot, so schedule a recheck at a regular interval, monthly for most sites, and after any major migration or redesign. Keeping broken links near zero protects both your visitors and the crawl efficiency that helps search engines index your best pages.

Frequently asked questions

What is the best free link checker?

For most sites, the free tier of Screaming Frog SEO Spider is the strongest option because it crawls internal and outbound links and reports every status code. The W3C Link Checker is a good no-install web alternative, and Google Search Console shows the broken URLs Google itself encounters. Combining a crawler with Search Console gives the most complete view.

What is the difference between a link checker and a backlinks checker?

A link checker crawls the links on your own pages and flags broken internal and outbound links. A backlinks checker looks in the opposite direction and shows which external websites link to yours. Both matter, but a link checker is about your site's internal health while a backlinks checker is about your off-site link profile.

How do I fix a broken internal link?

First find which of your pages contains the broken link using the source column in your crawl report. If the target page moved, update the link to the new URL or add a 301 redirect from the old address. If the target is gone for good, point the link to the most relevant live page or remove it.

Do broken links hurt my SEO?

Broken internal links waste crawl budget, trap visitors, and can leave good pages harder for search engines to reach. Individual 404s do not trigger a ranking penalty, but a site full of dead links signals neglect and delivers a poor user experience, so fixing them protects both usability and search performance.

How often should I run a link checker?

Run a full crawl about once a month for most sites, and always after a migration, redesign, or large content change. Links break continuously as pages are edited and external sites disappear, so a regular schedule keeps broken links near zero instead of letting them accumulate.