What it means
We flag pages with more than six stylesheets or synchronous scripts in the <head> that must load before the first paint.
Why it matters
Each blocking file adds a round trip before the first pixel appears, which delays First Contentful Paint and, usually, Largest Contentful Paint.
How to find it yourself
- PageSpeed Insights lists render-blocking requests and the time they cost.
- View the page source: <script src> without defer or async in the <head> blocks rendering.
How to fix it
On any website
- Add defer to scripts that don’t need to run before the page shows; use async for independent ones such as analytics.
- Inline the small amount of CSS needed for the top of the page and load the rest without blocking.
- Combine or remove stylesheets you don’t need on every page.
On Shopify
- Check theme.liquid and app snippets for scripts in the <head> without defer.
On WordPress and WooCommerce
- Use an optimization plugin to defer JavaScript and generate critical CSS, then test that nothing breaks.
How to check the fix
- Run the speed test again and compare the number of blocking files.
How FixReports finds it
The speed test counts stylesheets and synchronous scripts in the <head> of each page it tests.