Broken External Links: How to Find and Replace Dead Sources
Direct Answer
A third-party URL is broken when the intended source no longer resolves to useful content. Check the final destination and content, not only the first status code. Do not automatically replace an HTTP URL with HTTPS or a homepage unless you verify it is the same resource. For users, a link should communicate its destination and relationship. Developers should verify real href destinations, final responses, and appropriate rel values instead of only visible styling or anchor copy.
Documentation
What this check actually means
Request the final destination, then update to a moved source, replace it with equivalent evidence, or remove the unsupported citation.
A third-party URL is broken when the intended source no longer resolves to useful content. Check the final destination and content, not only the first status code. Do not automatically replace an HTTP URL with HTTPS or a homepage unless you verify it is the same resource.
Expected behavior and decision boundary
Expected state: A third-party URL is broken when the intended source no longer resolves to useful content. Check the final destination and content, not only the first status code. Do not automatically replace an HTTP URL with HTTPS or a homepage unless you verify it is the same resource. The real href, final destination resource, anchor text, and rel relationship match the actual editorial or commercial relationship.
Diagnosis: evidence to capture
Export source URL, link text, href, rel, target, first HTTP status, final URL, and final status. For third-party destinations, also verify that the final document is still the intended source.
Automated repair must not assume that HTTPS or a site home page is “probably correct” when the original resource has not been verified.
Technical implementation
A third-party URL is broken when the intended source no longer resolves to useful content. Check the final destination and content, not only the first status code. Do not automatically replace an HTTP URL with HTTPS or a homepage unless you verify it is the same resource.
<a href="https://example.org/original-study">Original study</a>
curl -IL https://example.org/original-study
Export source URL, anchor text, href, rel, target, final HTTP status, and final destination. For third-party links, automated “repair” must never assume a different document or an unverified HTTPS endpoint.
Concrete decision example
anchor,rel,first_status,final_url,final_status
Original study,"",301,https://publisher.example/research,200
Partner offer,sponsored,302,https://partner.example/landing,200
Then decide whether the final resource still represents the intended source or commercial relationship. A 200 status alone does not prove the destination is editorially correct.
Common root causes
Common causes include stale third-party sources, redirects to different content, CMS fields assigning the wrong rel, affiliate wrappers, copied links, generic anchor text, or JavaScript navigation without a dependable href. Inspect both markup and the final destination resource.
Edge cases and false positives
nofollow, sponsored, and ugc can be combined when more than one relationship applies. These attributes are not access-control mechanisms and do not stop users from opening a destination. A redirect is not automatically a broken link; verify whether the final resource is still the intended source.
Verification after the fix
| Check | PASS | FAIL | | --- | --- | --- | | Output | expected rule is visible in final HTML/HTTP/DOM | backend field looks correct but final output does not | | Scope | representative URLs from every affected template tested | only one example URL tested | | Source | shared root cause/owner is documented | manual per-page edits without root cause | | Regression | adjacent canonical/robots/accessibility/link rules still pass | fix creates a new defect in the same component | | Evidence | before/after values and test time are stored | only visual impression or screenshot |
Ownership and handoff
Content/SEO owner: defines the expected page purpose and whether the condition actually requires a change.
Developer/platform: fixes the shared template, routing, header, or component source.
QA: tests representative edge states and re-crawls/re-requests after deployment.
Release owner: records time, scope, and rollback point so monitoring signals can be tied to a specific change.
Acceptance criteria
PASS when the final technical state is reproducible on representative URLs, the shared root cause is fixed, intentional exceptions are documented, and a re-crawl/re-request shows no new regression in canonicalization, robots directives, accessibility, links, or rendering.
Questions & Answers
Should every external link use `nofollow`?
No. Normal editorial links do not need blanket nofollow. Use relationship attributes according to the real relationship.
How should paid links be marked?
Use rel="sponsored"; nofollow is also acceptable for paid links, but sponsored is more specific.
What is appropriate for user-generated links?
rel="ugc" can qualify the relationship, while moderation, spam controls, and security remain necessary.
Is a redirect destination automatically a broken link?
No. Verify the final resource. A redirect can be acceptable when it still reaches the intended source without a problematic chain.
Practical Check
- Define the affected URL/template class and write the expected behavior before changing anything.
- Capture raw HTTP/HTML; when client-side code changes output, also inspect the rendered DOM.
- Export final link destinations and relationship attributes as structured data.
- Trace the defect to its shared layer: DNS/CDN, routing, template, component, CMS field, or editorial content.
- Implement the smallest systemic fix and preserve a rollback point first.
- Test positive cases, missing/empty data, and at least one relevant edge state.
- Re-crawl or re-request every affected template/URL class and store before/after evidence.
- PASS: expected behavior is reproducible, no adjacent SEO/accessibility rule regresses, and the fix does not require manual per-page workarounds.