The Complete Guide to Eliminating Render-Blocking Resources in WordPress

Let me guess – you pulled up your site on PageSpeed Insights, only to discover that your precious WordPress site has render-blocking requests holding back its true speed potential.

Not to worry – with this comprehensive guide, you‘ll learn exactly how to diagnose render-blocking resources on your site and fix them using both manual optimizations and plugins for WordPress.

What Are Render-Blocking Resources and Why Do They Matter?

Before we dive into solutions, let‘s take a step back to quickly cover what render-blocking resources actually are and why you should care about optimizing them.

Render-blocking resources refer to external files like CSS, JS, and web fonts that must download and process before the browser can display page content to the user.

This delays the initial render, leading to blank loading screens that harm your site‘s perceived performance.

According to data from Akamai, a 1 second delay halves your conversion rates. Other studies have shown similar dramatic impacts on bounce rates and revenue metrics.

Clearly, optimizing the delivery of render-blocking assets correlates directly to your bottom line by facilitating faster rendering.

Identifying Render-Blocking Resources Hurting Your Site

The first step is running your homepage through PageSpeed Insights to pinpoint exactly which resources are currently blocking render:

PageSpeed Insights showing render-blocking CSS/JS

Pay attention here to any CSS/JS flagged by PageSpeed under "Eliminate render-blocking resources".

I also recommend running WebPageTest and examining the filmstrip view and Waterfall chart which visualize rendering over time. Any big gaps indicate assets that could be deferred instead.

For advanced testing, utilizing real user monitoring tools like SpeedCurve allows you to replay session recordings to distinguish which resources consistently delay First Paint in aggregate across actual visitors.

Manual Optimization Strategies and Code Examples

Before turning to plugins, let‘s explore some ways to manually optimize render-blocking requests:

1. Leverage async/defer for JavaScript

<!-- Async --> 
<script async src="script.js"></script>

<!-- Defer -->
<script defer src="script.js"></script> 

2. Split CSS By Media Queries

<link href="mobile.css" rel="stylesheet" media="screen and (max-width: 600px)">

<link href="desktop.css" rel="stylesheet">

3. Inline Critical CSS

  /* Critical CSS rules */

<link rel="stylesheet" href="main.css">

4. Self-Host Web Fonts

5. Remove Unused CSS/JS

6. Minify and Concatenate Code

See, optimizing render-blocking resources manually gives you precise control but requires expertise that‘s unrealistic for most site owners juggling 101 other priorities.

That‘s where purpose-built WordPress plugins can save the day…

Top WordPress Plugins for Render-Blocking Resources

Based on tons of testing and client projects, these are my top recommendations:

WP Rocket – Best Premium Plugin

WP Rocket goes far beyond basic caching…


  • Automatic critical CSS inlining
  • Asset optimization module
  • Premium support from performance geeks


  • Expensive at $199/year
  • Requires renewal every 12 months

Get WP Rocket

Autoptimize – Best Free Choice

For a free alternative, Autoptimize is shockingly fully-featured:


  • Open source & well supported
  • Easy interface for beginners
  • Broad browser cache leverage


  • Less configurability
  • Requires more fine-tuning

Get Autoptimize

W3 Total Cache vs Swift Performance

Both W3TC and Swift offer strong render-blocking optimization. However, Swift wins out with its automatic approach requiring less manual configuration.

In the end, I suggest testing 2-3 top options firsthand to understand which best accelerates your unique site and workflow.

Measuring Render-Blocking Optimization Impact

Of course, the proof is in the pudding when it comes to actually quantifying web performance gains…

After applying optimizations, I advise re-running PageSpeed Insights to validate improvements, monitoring load waterfall charts in WebPageTest to pinpoint bottlenecks, and leveraging Core Web Vitals to track real-world visitor metrics.

For ongoing insight, invest in mature analytics platforms such as Chrome UX Report or SpeedCurve which surface actionable perf diagnostics.

Additional WordPress Speed Tips

While render-blocking resources are low-hanging fruit, cascading performance wins require holistic optimization across hosting, code, databases, images, and beyond.

To take your site‘s speed to the next level, be sure to also:

  • Upgrade to a faster web host
  • Enable Redis or Memcached caching
  • Switch to PHP 7.4+
  • Resize/optimize images
  • Limit bloaty plugins

Visit my WordPress performance guide for more speed tips.

Now over to you – which render-blocking optimization resonated most from this guide? Let me know if you have any other questions!