Description
At a glance
Looking for Performance Lab v4.2.0? It is available here as a free GPL download for WordPress — 100K+ active installs · 4.3/5 rating from 51 reviews · updated August 26, 2026 · requires WordPress 6.9+ & PHP 7.4+.
The Performance Lab plugin is a collection of features focused on enhancing the performance of your site, most of which should eventually be merged into WordPress core. The plugin facilitates the discovery and activation of the individual performance feature plugins which the performance team is developing. In this way you can test the features to get their benefits before they become available in WordPress core. You can also play an important role by providing feedback to further improve the solutions.
The feature plugins which are currently featured by this plugin are:
- Embed Optimizer
- Enhanced Responsive Images
- Image Placeholders
- Image Prioritizer
- Instant Back/Forward
- Modern Image Formats
- Optimization Detective (dependency for Embed Optimizer and Image Prioritizer)
- Performant Translations
- Speculative Loading
- View Transitions (experimental)
These plugins can also be installed separately from installing Performance Lab, but having the Performance Lab plugin also active will ensure you find out about new performance features as they are developed.
Frequently asked questions
What do I get when I download Performance Lab?
Performance Lab 4.2.0 is the latest version. It is a WordPress plugin you can download here free of charge under the GPL license, with the complete feature set included and no trial limitations. It holds a 4.3/5 rating from 51 user reviews.
Does Performance Lab cost anything?
No. Performance Lab 4.2.0 is 100% free — the full GPL version, not a trial or demo. There are no download limits, no accounts to create, and no upsells during the download.
How do I install Performance Lab 4.2.0?
Download the ZIP file from this page, then in your WordPress dashboard go to Plugins → Add New → Upload Plugin, choose the file, click Install Now, then Activate. The plugin works immediately after activation — no license key or extra setup is required for the core features.
What are the requirements for Performance Lab?
Performance Lab 4.2.0 requires WordPress 6.9 or higher and PHP 7.4 or higher. Most modern WordPress hosts already meet these versions. Running older versions may cause features to break, so update WordPress and PHP first if your site is behind.
When was Performance Lab last updated?
Version 4.2.0 was last updated on August 26, 2026. This page is refreshed automatically, so the download here always matches the newest version we have verified.
Is the Performance Lab download safe?
The file is sourced directly from the official WordPress.org repository — the same file the developer published. It is served unmodified, so what you install here is byte-identical to the official release.
Technical details
| Version | 4.2.0 |
|---|---|
| Last updated | August 26, 2026 |
| Active installs | 100,000+ |
| Rating | ★★★★☆ 4.3/5 (51 reviews) |
| Requires WordPress | 6.9 or higher |
| Requires PHP | 7.4 or higher |
| Author | WordPress Performance Team |
| Tags | diagnostics, measurement, optimization, performance, site-health |
Download Performance Lab
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