WordPress 6.5 performance improvements

This post is the latest in a series of updates focused on the performance improvements of major releases (see 6.4, 6.3, and 6.2).

WordPress 6.5, “Regina” is the first major version of WordPress released in 2024. This release includes several important performance enhancements impacting the user experience for site visitors, along with remarkable improvements to editor performance. Importantly, WordPress 6.5 delivers site performance that is similar, if not superior to previous versions, despite the addition of many significant new features.

In our analysis of the Twenty Twenty-four theme, we observed modest changes in website front-end performance. The median LCP time shows a slight 0.81% decline in non-translated tests, with a 0.95% improvement in translated tests. Similarly, the Twenty Twenty-one theme exhibits a 1.13% drop in median LCP times in non-translated tests, yet showcases a notable 4.50% improvement in translated tests. Further details on the methodology behind these measurements are provided later in this article.

Key improvements

Improved performance for translated sites

This version of WordPress includes a new localization system that loads translationtranslation The process (or result) of changing text, words, and display formatting to support another language. Also see localization, internationalization. files more quickly, and introduces support for providing translation files as native PHPPHP The web scripting language in which WordPress is primarily architected. WordPress requires PHP 5.6.20 or higher files. As the merge announcement summarizes, these enhancements are expected to bring a 23.5% improvement in loading time and 41.4% reduction in memory consumption for translations.

A significantly faster editing experience

A major focus of this release was improving performance while editing your site. WordPress 6.5 delivers 5x faster typing processing, 2x faster editor loading, and a 60% reduction in pattern loading, based on measurements collected as part of the overall effort documented in this GitHub issue.

Improvements for registering blockBlock Block is the abstract term used to describe units of markup that, composed together, form the content or layout of a webpage using the WordPress editor. The idea combines concepts of what in the past may have achieved with shortcodes, custom HTML, and embed discovery into a single consistent API and user experience. variations

The WordPress block editing system allows blocks to be registered with a set of block variations, which makes it easy to define different versions of a block without needing to duplicate the whole block. This version of WordPress adds support for registering block variations only when used, avoiding costly processing when this data is unnecessary, which makes server rendering 5% faster.

Support for AVIF image format

WordPress 6.5 supports AVIF, a modern image format that offers significant improvements in image quality and compression over previous formats like JPEG, PNG, and even WebP.  AVIF images can be up to 50% smaller than JPEGs while maintaining the same image quality.

Additional performance focused changes

In total, there were 20 performance related improvements included in this release, split evenly between new enhancements (10) and bugbug A bug is an error or unexpected result. Performance improvements, code optimization, and are considered enhancements, not defects. After feature freeze, only bugs are dealt with, with regressions (adverse changes from the previous version) being the highest priority. fixes (10).

How release performance is measured

The performance measurements used for the overview are based on benchmarks1 conducted using an automated workflow on GitHubGitHub GitHub is a website that offers online implementation of git repositories that can easily be shared, copied and modified by other developers. Public repositories are free to host, private repositories require a paid subscription. GitHub introduced the concept of the ‘pull request’ where code changes done in branches by contributors can be reviewed and discussed before being merged be the repository owner. https://github.com/ action runners. Benchmarks were taken of the homepage of the Twenty Twenty-one, Twenty Twenty-three, and Twenty Twenty-four themes with and without translations installed, comparing WordPress 6.5 with WordPress 6.4.3 (the latest version of WP 6.4 available when 6.5 was released).

Performance metrics were collected from 100 runs for both CoreCore Core is the set of software required to run WordPress. The Core Development Team builds WordPress. Web Vitals (CWV) and Server-Timing headers provided by the Performance Lab pluginPlugin A plugin is a piece of software containing a group of functions that can be added to a WordPress website. They can extend functionality or add new features to your WordPress websites. WordPress plugins are written in the PHP programming language and integrate seamlessly with WordPress. These can be free in the WordPress.org Plugin Directory https://wordpress.org/plugins/ or can be cost-based plugin from a third-party using CLI scripts from the WPP Research repo.

Benchmark Data

No translation (en_EN):

Translation (it_IT):

Follow up from this release

Each release, the Performance Team looks for opportunities to improve the performance of WordPress for the following releases, which includes identifying ways we can improve the tooling and processes we use to support the performance practice. For example, we’re collecting opportunities to improve our performance testing in this GitHub issue

You can also follow progress on other performance-related work being planned for the WordPress 6.6 release in Trac and in the Gutenberg repository. A full list of the Performance Team’s priorities for the year is available on the 2024 Roadmap page in the team’s handbook. Come join us in making WordPress as performant as possible.

Props to @flixos90, @peterwilson, @adamsilverstein, @annezazu, and @jorbin for contributing to this post.

  1.  Benchmark measurements use lab data to gather performance metrics under controlled conditions and may not reflect the way the software performs in the field. For more on the differences between Lab and Field data, see this article. ↩︎

#6-5, #core, #core-performance, #performance