Optimize Unused CSS and JavaScript

How to optimize learn.wowlearnings.org

Next.js SiteScore: 84/100Analyzed May 2026Re-analyze this site

Optimize Unused CSS and JavaScript

Medium Impact+8 points estimated

Why It Matters

Over 284KB of unused JavaScript and 29KB of unused CSS are being downloaded unnecessarily.

How to Fix

Enable Next.js tree-shaking by using ES6 imports and avoiding default exports where possible. Remove unused CSS by auditing the 93% unused styles in the main CSS file. Use next-unused to identify and remove dead code from your React components.

0Needs Improvement

What This Score Means

A score of 84 falls in the "Needs Improvement" range (50-89). While it is better than poor (0-49), you should aim for 90+ to provide an optimal user experience and maximize SEO benefits.

This site is slower than approximately 35% of similar sites. The main issues affecting performance are image optimization, JavaScript execution time, and layout stability.

Addressing these issues could improve your conversion rate by 15-20% and boost your search engine rankings.

Core Web Vitals Analysis

LCP

Largest Contentful Paint

2.2s
Good

Good: < 2.5s

Measures how long it takes for the main content to appear on screen

INP

Interaction to Next Paint

190ms
Good

Good: < 200ms

Measures how quickly the page responds to user interactions

CLS

Cumulative Layout Shift

0.01
Good

Good: < 0.1

Measures visual stability - how much content shifts during page load

AI Performance Analysis

This Next.js/React site has good but not optimal performance with a score of 84/100. The biggest problem is excessive JavaScript execution taking 2.1 seconds, which is blocking user interactions and causing an 8.7-second delay before the page becomes fully interactive. The site is loading 284 KB of unused JavaScript code and has render-blocking CSS files that delay initial page rendering by 530ms. Reducing JavaScript bundle sizes, removing unused code, and deferring non-critical CSS could improve the score significantly and make the site much more responsive for users.

Other Optimization Recommendations

Eliminate Render Blocking CSS

High Impact+12 points estimated

Why It Matters:

CSS files are blocking initial page render and delaying both LCP and FCP by 530ms.

How to Fix:

Inline critical CSS directly in the Next.js page component using styled-jsx or CSS-in-JS. Use next/dynamic with ssr: false for non-critical styles. Split the large 31KB CSS file into smaller, page-specific chunks using CSS modules.

Reduce JavaScript Execution Time

High Impact+15 points estimated

Why It Matters:

JavaScript execution takes 2.1 seconds and creates 420ms of Total Blocking Time, severely impacting interactivity.

How to Fix:

Use Next.js dynamic imports to code-split large chunks like 0cnk-vj-0hm9p.js. Remove unused JavaScript polyfills for modern browsers (40KB savings available). Defer Google Tag Manager loading until after page interaction using next/script with strategy='lazyOnload'.

Keep Your Site Fast After Optimization

Once your site is optimized, maintain that speed. Use DeployHQ for zero-downtime, automated deployments—so performance fixes and updates go live safely every time, without breaking your site.

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