Passing Core Web Vitals: A Mobile Speed Overhaul for a Publisher
Client: A high-traffic news and media publisher on WordPress.
Challenges We Faced
The client’s mobile traffic was declining due to a recent Google Core Update that penalized slow sites:
Failing Core Web Vitals
The site was failing all three metrics (LCP, INP, CLS) on mobile.
Slow Mobile LCP
Large hero images and video ads were causing an 8-second load time on 4G networks.
Ad-Related CLS
Programmatic ads were loading late and shifting the content, causing a poor user experience.
Bloated Code
The site had 40+ active plugins, many loading unused CSS and JS on every page.
Low Mobile Engagement
Users were bouncing before the articles could even load.
Pass Your Core Web Vitals
“Is your slow mobile site killing your rankings? Our Core Web Vitals Optimization service will get you in the ‘Good’ zone.”
Our Approach – How We Solved These Challenges
Comprehensive Mobile Speed Audit
We used Google PageSpeed Insights and WebPageTest to identify the specific scripts and images slowing down the site.
Code Minification (CSS, JS, HTML)
We audited all 40 plugins, removed 15 unused ones, and used WP Rocket to minify and defer the remaining JavaScript.
Core Web Vitals Optimization
We fixed the CLS issue by reserving fixed height/width containers for all ad slots in the CSS.
We improved LCP by pre-loading the “hero” image and lazy-loading all other images and iframes.
Technical Server Optimization
We upgraded their hosting to a dedicated server and implemented Redis object caching to reduce the TTFB (Time to First Byte).
Results
| Metric | Before | After | Growth |
|---|---|---|---|
| Mobile PageSpeed Score | 22 (Poor) | 91 (Good) | +313% |
| Core Web Vitals (Mobile) | “Failing” | “Passing” (All 3) | Passed |
| Mobile Organic Traffic | 1.2M/mo (Declining) | 1.5M/mo (Recovering) | +25% |
Free Mobile Speed Audit
“Not sure why your site is slow? Claim a Free Mobile Speed Audit and let our mobile page speed optimization company find the problem!”
Advice for Marketers & Brand Owners
- Ads kill speed. You must optimize how your ads load. Reserve space for them to stop layout shifts (CLS).
- Audit your plugins. Every plugin adds code. If you don’t use it, delete it.
- Hosting matters. A slow server (high TTFB) will make your site slow no matter how much you optimize the code.
- Mobile users are impatient. Every second of load time increases bounce rate by over 10%.
Extra Factors That Made It Work
- The WP Rocket configuration was the biggest “quick win” for code minification.
- Upgrading the server infrastructure solved the backend bottlenecks.
- Fixing the ad-related CLS improved the user experience immediately, leading to longer session durations.
