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Statically analyze href attributes and pasted URLs for javascript: pseudo-links, odd schemes, and other red flags - pair with real crawls for HTTP status.
Quick answer: Broken Link Pattern Checker
Static scan for risky href schemes and malformed URLs before you pay for a full crawl.
Example: Paste landing HTML → flag `javascript:void(0)` CTA, OK relative `/pricing` paths, OK `mailto:` support links.
Calculations follow the documented formula on this page; rounding and input units can change the last digit-treat outputs as educational estimates unless you reconcile with source systems.
* This is an estimate. Actual amounts may vary slightly based on input assumptions.
javascript: and odd protocols break accessibility and SEO flows; this flags obvious foot-guns, not remote 404s.
Statically analyze href attributes and pasted URLs for javascript: pseudo-links, odd schemes, and other red flags - pair with real crawls for HTTP status.
Inputs on this page: HTML (optional), Extra URLs (one per line, optional). Assumptions stay visible so you can reproduce the figure elsewhere.
Long-form walkthroughs that pair well with this calculator. When you need narrative context beyond the live fields, start here and return to the tool to plug in your own numbers.
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Read guide →People who care about broken link checker use Broken Link Pattern Checker as a planning sandbox: Trackers sometimes rewrite URLs - inspect final HTML, not just CMS preview.
Continue in the Developer category hub, the Developer tools collection, or the glossary. Related calculators in this session: URL Encoder/Decoder, Regex Tester, .htaccess Redirect Generator, Meta Tag Analyzer, Robots.txt Generator, JSON Formatter.
The Formula
Flag non-http(s)/mailto/tel/relative href patterns including javascript: pseudo-links| This tool | Flag non-http(s)/mailto/tel/relative href patterns including javascript: pseudo-links |
|---|---|
| Related intent: broken link checker | See paired tools for broken link checker-each page documents its own core relationship next to the live form. |
| Related intent: html link validator | See paired tools for html link validator-each page documents its own core relationship next to the live form. |
Core relationship for Broken Link Pattern Checker:
Flag non-http(s)/mailto/tel/relative href patterns including javascript: pseudo-links
Worked check: Paste landing HTML → flag `javascript:void(0)` CTA, OK relative `/pricing` paths, OK `mailto:` support links.
Keep the same assumptions and open a neighbor calculator when your question branches: URL Encoder/Decoder, Regex Tester, .htaccess Redirect Generator, Meta Tag Analyzer. Each page documents its own formula beside the fields.
Learning links: Methodology · Editorial policy · Glossary
Paste landing HTML → flag `javascript:void(0)` CTA, OK relative `/pricing` paths, OK `mailto:` support links.
Re-enter the same numbers in the calculator above to confirm the page math matches the interactive result.
People who care about broken link checker use Broken Link Pattern Checker as a planning sandbox: Trackers sometimes rewrite URLs - inspect final HTML, not just CMS preview.
Instant response
Run Broken Link Pattern Checker in the browser and read the breakdown beside the form.
Transparent formula
The formula and worked example on this page match what the calculator uses.
Privacy friendly
No account required; inputs stay in your session unless you choose to share them.
Cross-device ready
Layout works on mobile, tablet, and desktop for the same field labels.
Official references for context. Calculator outputs are planning estimates—confirm material decisions with the primary authority or a qualified professional. See our methodology and editorial policy.
Reviewed July 18, 2026 · Content stamp 2026-07-18
Click a question to expand the answer.
Yes, the Broken Link Pattern Checker is completely free with no hidden limits.
Yes. All tools are optimized for desktop, tablet, and mobile devices.
No - this is a pattern scan only; it cannot detect remote 404 responses.
Yes - root-relative and ./../ paths are treated as acceptable patterns.
mailto: and tel: links are allowed as common patterns.
Static scan for risky href schemes and malformed URLs before you pay for a full crawl.
Paste landing HTML → flag `javascript:void(0)` CTA, OK relative `/pricing` paths, OK `mailto:` support links.
Trackers sometimes rewrite URLs - inspect final HTML, not just CMS preview. Empty hrefs are clickable traps - use buttons for actions instead. Pair with log-based 404 monitoring after launches.
Same-category picks first, then high-intent neighbors that often answer the next calculation question.
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Open the full directory, browse your hub collection, or jump back to this category. Bookmark the page if you use it often.
Reviewed by Imtiaz Ahmad
Founder & lead engineer | Last reviewed July 18, 2026
See methodology and editorial policy.