How to Defer Parsing of JavaScript in WordPress

In this article, we will show you how to defer parsing of JavaScript in WordPress to improve your website’s loading speed.

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Why defer parsing of JavaScript?

There are many reasons why you would want to defer parsing of JavaScript in WordPress. The most common reason is to improve your WordPress site’s speed. When a browser loads a webpage it has to parse the HTML, CSS, and JavaScript to render the page. If your HTML and CSS are not minified and your JavaScript files are not small, then it can take the browser a lot of time to parse and render the page. By deferring parsing of JavaScript you can reduce the time it takes to render the page.

Another reason why you might want to defer parsing of JavaScript is because you are using a WordPress plugin that is slowly loading your website. If you defer parsing of JavaScript then it can help improve your website’s speed.

How to defer parsing of JavaScript in WordPress?

One way to speed up your WordPress site is to defer parsing of JavaScript. By doing this, you can reduce the number of HTTP requests and improve the loading time of your pages.

There are a few ways to defer parsing of JavaScript in WordPress. One way is to use the Async JavaScript plugin. This plugin will asynchronously load your JavaScript files, which means that they will be loaded in the background while your page is loading. Another way to defer parsing of JavaScript is to use the Defer JS plugin. This plugin will defer the loading of your JavaScript files until after your page has finished loading.

You can also defer parsing of JavaScript by using a WordPress theme that is designed for speed. Some themes, such as Thesis, have built-in options for deferred loading of JavaScript files.

If you are not using a WordPress theme that has built-in options for deferred loading of JavaScript, you can still add this functionality to your site by using a WordPress plugin such as Async Javascript or Defer JS.

What are the benefits of deferring parsing of JavaScript?

There are several benefits to deferring parsing of JavaScript, including:

-Reduced load time: Deferring parsing of JavaScript can reduce the amount of time it takes for a page to load. By deferring parsing of JavaScript until after the page has loaded, you can reduce the number of resources that need to be loaded simultaneously.

-Increased compatibility: Deferring parsing of JavaScript can increase compatibility with older browsers and devices. By deferring parsing of JavaScript, you can ensure that your website will work with a wider range of devices and browsers.

-Improved search engine optimization: Deferring parsing of JavaScript can improve your website’s search engine optimization (SEO). By deferring parsing of JavaScript, you can ensure that your website’s content is visible to search engines and can be properly indexed.

How does deferring parsing of JavaScript improve performance?

Delaying the loading of JavaScript can give the browser time to load other more critical resources first. By deferring parsing of JavaScript you can improve the loading performance of your page.

The challenge with JavaScript is that it is often loaded in the head of the document, which can delay the loading of other content in the page. By deferring parsing of JavaScript you can improve the loading performance of your page.

There are a few different ways to defer parsing of JavaScript in WordPress. One way is to use the async attribute onscript tags. This will tell the browser to load the script as soon as it has time and will not delay other content on the page:

Another way to defer parsing of JavaScript is to use a plugin like WPRocket or Autoptimize, which can optimize your WordPress website’s performance by minifying and concatenating your CSS and JavaScript files, as well as Deferring Parsing of JavaScript.

What are the drawbacks of deferring parsing of JavaScript?

There are a few potential drawbacks to deferring parsing of JavaScript:

1. If your JavaScript files are large, it can take longer for the browser to download and parse them.
2. If your JavaScript relies on external resources (such as jQuery), those resources may not be available when the browser tries to parse your code.
3. Some browsers (e.g., older versions of IE) do not support deferring parsing of JavaScript.

Overall, deferring parsing of JavaScript can improve page load times, but it is not always the perfect solution for every site.

How to troubleshoot issues with deferring parsing of JavaScript?

If you are having issues with deferring parsing of JavaScript, there are a few troubleshooting steps you can take.

1. First, make sure that you are using the latest version of WordPress. Older versions of WordPress may not support deferring parsing of JavaScript.

2. If you are using a caching plugin, clear your cache and try again.

3. Try deactivating all plugins except for defer-javascript and see if that solves the issue. If so, then one of your other plugins is causing a conflict. Try activate each plugin one at a time to isolate the issue.

4. If you are still having issues, contact the defer-javascript support team for help.

Is deferring parsing of JavaScript always the best option?

The defer attribute is a Boolean attribute, which means that if it is present, it must have the value defers.

The purpose of the defer attribute is to specify that the script is meant to be executed after the document has been parsed. By deferring execution to after the document is parsed, multiple scripts can be included and run sequentially. This eliminates potential issues caused by scripts running out of order.

The async and defer attributes are similar in that they both allow scripts to run asynchronously. The difference is that with async, the script will execute as soon as it’s loaded, whereas with defer, the script will execute when the document has been parsed.

There are some advantages to using defer over async, such as:
-Scripts load in order: If you have several scripts that need to run sequentially, you can use the defer attribute to ensure they run in the correct order. With async, there’s no guarantee that your scripts will execute in the order you want them to.
-Scripts don’t block rendering: Because asyncScripts don’t block rendering, they can improve your page’s performance. With deferScripts, rendering is blocked until all scripts have finished loading, so there’s potential for a performance hit.

What are some other ways to improve WordPress performance?

Other ways to improve WordPress performance include:
– Use a content delivery network (CDN)
– Optimize your images
– Minimize HTTP requests
– Use caching
– Minimize the use of plugins
– Upgrade to a faster hosting plan

Conclusion

In conclusion, deferring parsing of JavaScript can be a great way to improve your WordPress site’s loading speed. By deferring parsing of JavaScript, you can ensure that your site’s content is loaded first, before any JavaScript code is executed. This can help to improve your site’s overall loading speed, as well as improve your user’s experience.

Further Reading

If you want to learn more about how to defer parsing of JavaScript in WordPress, we recommend checking out the following resources:

-The Official WordPress documentation on [Optimizing JavaScript](https://make.wordpress.org/support/handbook/optimizing-javascript-for-loading/)
-A comprehensive guide on [How to Defer Parsing of JavaScript](https://www.keycdn.com/blog/defer-parsing-of-javascript/) by keyCDN
-An article on [6 Ways to Improve Your WordPress Site’s Page Load Times](https://themeisle.com/blog/improve-page-load-time/) by ThemeIsle