How to Load Third-Party JavaScript Asynchronously

Web browsers will often attempt to load any requested JavaScript files before they actually start to render the web page content, which can lead to long wait times before users can interact with a website. JavaScript files are generally not needed to start rendering web pages and delaying their retrieval can help improve the overall user experience.

JavaScript files can be marked with the async and defer tags to tell the web browser to hold off on downloading the JavaScript files until after more important files and information have finished loading.

WordPress websites can use plugins to make included JavaScript files load asynchronously without requiring any manual administration. Speed Coach also will identify instances of synchronously loading JavaScript files in case there are plugins or files that are slowing down website loading performance and need to be addressed.