How We Scored 100/100 on Mobile PageSpeed for a 35K-Product WooCommerce Store with WP Rocket (And How You Can Too)

In the last few weeks, our team at Oxford Metadata achieved what many consider impossible: a 100/100 mobile PageSpeed Insights score on a 35,000-product WooCommerce store—while boosting monthly turnover ×4 vs. its Magento days and exceeding even our lockdown “ultimate intent” highs.

Table of Contents

• Why Optimize for Speed?
• Why Focus on WooCommerce?
• Why Focus on Mobile?
• Challenge
• WP Rocket in Action: 5 Features That Take You to 95/100
• Going the Extra Mile: Advanced Tuning
• The 100/100 Secret: Perfecting Your LCP Image
• Results
• Bottom-Line Impact: Magento → WooCommerce
• Tips from the Experts
• Eshop-Optimizer: Free Site-Performance Audit
• About the Author
• Ready to Supercharge Your Store?

Why Optimize for Speed?

Because it’s fun!
Solving for PHP execution, database queries, critical CSS, asset delivery, and third-party scripts—each improvement uncovers fresh bottlenecks. It’s a true engineering playground.

Because of the community.
Speed enthusiasts share configs, benchmarks, and friendly challenges in Slack, GitHub, and at WordCamps. We all rise together.

Because clients reap massive rewards.
Faster sites reliably deliver higher conversions, lower bounce rates, and happier shoppers—often exceeding expectations by orders of magnitude.

Why Focus on WooCommerce?

• Dynamic content everywhere. Product listings, carts, checkouts, and AI recommendations—all uncached by default.
• Complex business logic. Inventory checks, sessions, upsells, cross-sells, and AI recommendations introduce runtime overhead.
• Heavy media. Galleries, sliders, and variant swatches inflate payload sizes.

If you can serve a 35K-product shop in under a second on mobile, any other site is child’s play.

Why Focus on Mobile?

• Up to 90% of e-commerce orders happen on phones in many markets.
• Stricter lab metrics. A 100/100 desktop score typically translates to ~90 on mobile.
• Real-world constraints. CPU throttling, limited memory, and network variability make mobile the ultimate proving ground.
• Company culture litmus test. If your client cares about mobile performance, they truly care about their customers.

Challenge

Our client’s WooCommerce store—with 35K products, 120 active plugins, and dynamic AI recommendations—was averaging:

• Mobile PSI: ~55/100
• LCP: 3.2 s
• €/session: €0.20 (Magento era)

“We needed sub-second mobile loads without sacrificing any of our rich WooCommerce features.”

WP Rocket in Action: 5 Features That Take You to 95/100

1. Mobile Cache & Preload
   Enable a dedicated mobile cache and preload it via your XML sitemap so visitors always hit a warm page.
2. Remove Unused CSS (RUCSS)
   Strip out CSS rules your page never uses—keeping your stylesheets lean and fast.
3. Minify & Combine CSS/JS
   Reduce HTTP requests and overall payload by minifying and concatenating files.
4. Delay JavaScript Execution
   Postpone non-critical scripts (analytics, chat widgets) until user interaction.
5. Optimize CSS Delivery
   Generate and inline “critical path” CSS so above-the-fold content renders instantly.

Going the Extra Mile: Advanced Tuning

1. Preload LCP & Fonts
   Hard-code <link rel="preload"> for your hero image and WOFF2 font files to fetch them first.
2. Font Subsetting & Self-Hosting
   Subset Google Fonts to only the codepages you need (Latin+Greek → 25 KB) and serve them from your domain to eliminate external DNS lookups.
3. DNS-Prefetch & Preconnect
   Add <link rel="preconnect"> and <link rel="dns-prefetch"> for any third-party domains (analytics, tag managers) to shorten handshake times.
4. DOM Reduction & LazyLoad HTML Blocks
   Use WP Rocket to lazy-load static elements like mega-menus, sliders, and footers so they don’t bloat your initial DOM.
5. Plugin Organizer
   Load payment, checkout, and analytics scripts only on the pages that need them to avoid firing heavy code everywhere.
6. Filesystem & Image Distribution
   Don’t dump millions of files in one folder—use date-based subdirectories, and serve images from a cookie-free domain (e.g., i.yourshop.com).

The 100/100 Secret: Perfecting Your LCP Image

“Our lab site scored 100/100 with a simple 350×622 px test image. The live site stayed at 99/100 until we trimmed and preloaded our production hero image.”

Key Difference: identical dimensions (350×622 px), but our production image had gradients, text overlays, and complex patterns that added decode time. By simplifying and preloading it, we closed that final gap.

add_action( 'wp_head', 'ff_preload_mobile_image', 1 );
function ff_preload_mobile_image() {
  if ( ! is_front_page() || ! wp_is_mobile() ) return;
  $img = '/wp-content/uploads/2025/06/lcp-image-simple.webp';
  echo '<link rel="preload" as="image" href="' . esc_url( $img ) . '" media="(max-width:767px)" importance="high">';
}

Results

Bottom-Line Impact: Magento → WooCommerce

Tips from the Experts

Eshop-Optimizer: Free Site-Performance Audit

Given today’s speed imperatives, Oxford Metadata launched Eshop-Optimizer:

• Free, no-strings audit of your WooCommerce/WordPress store
• In-depth PSI & GTmetrix report
• Core Web Vitals field-data insights
• Prioritized action plan: server, CDN, WP Rocket, code

Sign up now for your free audit →

About the Author

Dimitris Vayenas is founder and principal consultant at Oxford Metadata (UK). With 45 years in computing and 30 years building web applications since 1995, he lives for hands-on performance tuning. Oxford Metadata uses ML-driven static code analysis and GraphDB visualizations (Neo4j, OrientDB) to power secure, high-performance apps in finance, defense, and healthcare.

Ready to Supercharge Your Store?

• Install or update WP Rocket (350K+ users can’t be wrong).
• Sign up for your free Eshop-Optimizer audit.
• Apply our step-by-step guide and watch your mobile PSI soar to 100.

Because in e-commerce, milliseconds matter—and the payoff is life-changing.