# How to reduce unused JavaScript

> JavaScript that is downloaded but never runs still costs bandwidth, parsing and memory on phones. Split bundles, drop dead plugins and load features on demand.

Speed & Core Web Vitals · HTML version: https://getreport.app/learn/unused-javascript

## Unused JavaScript

Passing looks like: Little unused JavaScript is downloaded.

**Why it matters.** JavaScript is the most expensive thing a page loads — it must be downloaded, parsed and run. Code that never executes still costs all of that on a phone.

**How to fix it.**

1. Delay third-party scripts until interaction (WP Rocket "Delay JavaScript", Shopify: audit installed apps).
2. Code-split large bundles so each page loads only its own code.
3. Remove plugins, apps and tags you no longer use.

Check your own page: https://getreport.app/