Page Speed Optimization

Euronics' Shopify Plus Site Speed Optimization: A Detailed Technical Case Study


Euronics embarked on a crucial optimization initiative to enhance their Shopify Plus site's speed, focusing on vital metrics like Largest Contentful Paint (LCP), First Contentful Paint (FCP), and Total Blocking Time (TBT).

Audit Overview and Initial Findings:

The comprehensive audit of Euronics' website pinpointed several key areas affecting performance, with a notable focus on JavaScript execution time, excessive DOM size, large network payloads, and inefficient cache policies. Key initial metrics included an LCP of 5.8s, FCP at 1.1s, and a TBT of 2.6s, highlighting the need for substantial improvements.

Optimization Strategies:

JavaScript Execution Time:

  • The site's JavaScript execution time was significantly reduced by optimizing and deferring the loading of scripts, removing unused JavaScript, and minimizing main-thread work.
  • Specific actions included minifying JavaScript files, removing unnecessary third-party scripts, and implementing async and defer attributes to non-essential JS.

DOM Size Reduction:

  • Addressed the excessive DOM size by streamlining HTML structure, removing redundant nodes, and optimizing CSS to reduce render-blocking resources.
  • Enhanced site structure by implementing lazy loading for images and offscreen content, significantly improving interactive times.

Network Payloads and Cache Efficiency:

  • Optimized image sizes, employed next-gen formats, and adjusted the compression settings to reduce the network payload.
  • Improved caching policies by leveraging browser and server-side caching, ensuring efficient static asset delivery.

Reducing Total Blocking Time (TBT):

  • Focused on minimizing long tasks, breaking down complex processing tasks into smaller, more manageable chunks to reduce TBT.
  • Employed web workers for off-thread execution of heavy JavaScript tasks, ensuring the main thread remains unblocked and more responsive.

Results and Impact:

After the implementation of these optimization strategies, Euronics witnessed remarkable improvements:

  • LCP improved from 5.8s to below 2.5s, aligning with best practice benchmarks.
  • FCP was enhanced from 1.1s to under 1s, significantly boosting the perceived speed of the site.
  • TBT was reduced from 2.6s to under 300ms, contributing to a smoother, more responsive user experience.


This case study exemplifies the profound impact of targeted optimizations on a Shopify Plus site's performance. Euronics' commitment to enhancing their site's speed has not only improved user experience but is also poised to positively influence their conversion rates and SEO rankings, demonstrating the tangible benefits of a data-driven approach to site speed optimization.