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🐛JavaScript Analysis: Find Render-Blocking JS Errors
Google can't rank what it can't render, and JavaScript errors are often the hidden reason pages underperform. This audit crawls multiple pages to surface console errors, warnings, and render-blocking issues that most audits miss entirely.
Who it's for
- Developers debugging render issues
- SEOs chasing unexplained ranking drops
- Teams running JS-heavy frameworks
What you get
- Multi-page console error detection across your site
- Up to 50 pages per run, each opened in a real browser
- Render-blocking resource identification and severity categorization
- Performance impact assessment and Core Web Vitals impact scoring
- Third-party script impact analysis and lazy loading checks
- Framework-specific issue detection for React, Vue and Angular
- Unused JavaScript detection to trim dead weight
How it works
- Enter your website URL
- We crawl pages and capture JS errors
- Get a prioritized issue report
Sample insight
💡 A third-party script throws console errors on several pages and blocks rendering, delaying when key content becomes visible and dragging down Core Web Vitals.
Frequently asked questions
Why do JavaScript errors hurt SEO?
If JavaScript fails to render, Google may not see your content. This audit surfaces the console errors and render-blocking issues that quietly cost rankings.
Does it work with my framework?
Yes. It includes framework-specific issue detection for React, Vue and Angular, alongside general console and render-blocking checks.
Can I check more than one site?
Yes — paste up to 50 page URLs per run, from one site or several, and each page is checked for console errors and render-blocking JavaScript.
What does unused JavaScript detection do?
It flags JavaScript that loads but isn't needed, so you can remove dead weight and improve performance and Core Web Vitals.