How to Use 'JavaScript' Application?

The JavaScript application lets you quickly optimise your JavaScript files by offering features such as minification, bundling, SmartJS and preloading, improving the loading performance and user experience of your website.

Find out more about the pitfalls to avoid when optimising JavaScript loading.

How do I use the "Javascript" application?

JavaScript Minification

JavaScript minification consists of reducing the size of JavaScript files by removing spaces, comments and other non-essential characters. 

Fasterize performs this basic minification automatically, which helps to reduce bandwidth consumption and script analysis time.

Bundle

The JavaScript Bundling option allows several external scripts to be combined in as few files as possible, reducing network response times (RTTs) and delays in downloading other resources. This consolidation helps to speed up page loading and improve the user experience.

SmartJS

The SmartJS option defers the loading of uncalled JavaScript functions at start-up, reducing the initial download size and enabling other resources to be downloaded in parallel, speeding up execution and rendering times.

Preload

The Preload option adds a rel=preload link for deferred scripts, allowing the necessary JavaScript files to be preloaded before they are executed. This reduces the waiting time when pages are loaded by anticipating the downloading of important resources.

Webperf advantage

Deferring the execution of JavaScript allows you to give priority to the resources needed for rendering (CSS, Images).

This can boost your FCP, speed index and LCP.

Reducing the size of JS resources means they can be downloaded and executed more quickly. Grouping JS scripts together optimises the number of requests.