Render-blocking Resources
Find stylesheet and sync script candidates that can delay first paint.
Performance and page weight
Last reviewed Nov 11, 2026
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Enter a URL to find potentially render-blocking CSS/JS.
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Encoding
Identity bytes
Savings
%
HTML
Sampled assets
Estimated total
Assets found
Heaviest sampled assets
| Type | Bytes | URL |
|---|---|---|
Blocking CSS ()
Blocking JS ()
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FAQ
Yes. Fair-use rate limits keep the suite available for everyone.
Yes. CDNs, registry redaction, and heuristics mean you should verify critical findings in your own environment.
Runs are processed to return results. Avoid pasting secrets or personal data you would not put in a public tool.