Avoid render-blocking resources


This audit identifies resources (specifically scripts and stylesheets) which are delaying the loading of ad tag libraries. These are resources that were requested and received before ad tag libraries began loading. Reducing the number of resources requested prior to tag load will speed up ad loading.


The details of this audit contain a list of all scripts and stylesheets that are delaying tag load. The goal is to reduce the number of entries in this list as close to 0 as possible. Some tips for doing this include:

  • Loading ad tag libraries earlier in the <head> of the page.
  • Inlining scripts and stylesheets critical to core functionality directly into your HTML.
  • Marking non-critical scripts with the async or defer attributes.
  • Separating styles into different files by media query and using the media attribute to load them only when needed.

More information

The following ad tag library scripts are supported:

Library Script(s)



Google Publisher Tag



Rendering Blocking Resources