The world’s most popular content management system (CMS) has been WordPress for years. In early 2021, it powered about 40% of web sites on the internet. Usually speed – how quickly pages load on user’s screen – is a key factor for choosing a CMS software, but if it was the only factor, Drupal would be the most used CMS.
The results from the performance tests don’t necessarily give one clear answer, because a CMS can perform well in one test but poorly in another test. In any case, the conclusion from the tests of five CMS is:
- Drupal is the fastest CMS software.
- Wix is the slowest.
- WordPress, Joomla and Squarespace rank in the middle category.
Let’s look at the tests to understand how each CMS performed. The test suite was developed by Google, called Core Web Vitals.
What is Core Web Vitals?
The Core Web Vitals focuses on the user experience, is measurable in the field, and reflects the real-world experience of a critical user-centric outcome. The current measurement set for 2020 focuses on three aspects of the user experience: loading, interactivity, and visual stability. It includes the following metrics:
- Largest Contentful Paint (LCP) measures loading performance. To provide a good user experience, LCP should occur within 2.5 seconds of when the page first starts loading.
- First Input Delay (FID) measures interactivity. To provide a good user experience, pages should have a FID of less than 100 milliseconds.
- Cumulative Layout Shift (CLS): measures visual stability. To provide a good user experience, pages should maintain a CLS of less than 0.1.
You can see yourself how it works and measure your web sites with the Pagespeed Insights tool.
The differences of these test categories indicate the differences between CMS products.
LCP (Largest Contentful Paint) test scores
Higher percentage is better:
- Drupal 47%
- Joomla 38%
- WordPress 25%
- Squarspace 12%
- Wix 9%
FDI, First Input Delay, scores
- Squarespace 91%
- WordPress 88%
- Drupal 76%
- Joomla 71%
- Wix 46%
CLS Cumulative Layout Shift scores
- Drupal 70%
- Joomla 63%
- Wix 59%
- WordPress 57%
- Squarespace 44%