Open Source vs. Proprietary: Which Wins on Core Web Vitals?

A recent analysis of website performance reveals a striking trend: proprietary platforms are currently outpacing their open-source counterparts when it comes to meeting Google’s Core Web Vitals standards. The latest data from the HTTPArchive community’s Core Web Vitals Technology Report, covering November 2025, shows a dramatic performance gap. The highest-ranked content management system achieved an impressive 84.87% of sites passing CWV, while the lowest-ranked platform managed only 46.28%. This nearly forty-point difference highlights a significant disparity in how effectively different systems deliver fast, stable user experiences.

What makes this snapshot particularly interesting is the clear division between platform types. The top three performers were all closed-source, proprietary systems. Open-source platforms occupied the bottom three positions. This pattern suggests that centralized control over a platform’s architecture and hosting environment may provide a tangible advantage in optimizing for these critical user experience metrics.

Core Web Vitals are a set of specific metrics developed by Google to quantify real-world user experience. They measure how quickly a page loads, becomes interactive, and remains visually stable. Sites that excel in these areas tend to keep visitors engaged longer, leading to better outcomes for conversions, readership, and overall business goals. Conversely, poor performance frustrates users, increases bounce rates, and undermines a website’s effectiveness. These scores offer a valuable, data-driven reflection of how a site performs under actual browsing conditions.

The report’s findings are derived from a combination of two major public data sources. The first is the Chrome UX Report (CrUX), which aggregates anonymous performance data from users who have opted to share their browsing statistics. This provides a genuine picture of real-user experiences across the web. The second source is the HTTP Archive itself, which conducts automated, lab-based tests on millions of sites to analyze how they are built and whether they adhere to modern performance best practices. By merging these datasets, the report creates a comprehensive performance snapshot for each major content management system.

Duda emerged as the clear leader in the November 2025 rankings. An outstanding 84.87% of sites built on its platform earned a passing Core Web Vitals score. This made Duda the only system in the comparison where more than four out of five sites met the threshold. The platform has maintained this top position for several consecutive years, demonstrating a consistent commitment to performance.

Wix secured the second-place spot, with 74.86% of its sites passing CWV. While it trailed Duda by a notable margin, it held a comfortable lead over the third-place contender. Squarespace followed closely in third, achieving a 70.39% pass rate. Its performance placed it nearer to Wix than to the next platform on the list, solidifying the top three as a distinct tier of proprietary site builders.

The rankings then transitioned to open-source systems. Drupal ranked fourth with a 63.27% pass rate, placing it squarely in the middle of the pack but notably below the three proprietary leaders. Joomla came in fifth at 56.92%, meaning just over half of its sites met the performance standards.

WordPress, the world’s most popular CMS, ranked last. Only 46.28% of WordPress sites passed Core Web Vitals in this analysis, lagging behind fifth-place Joomla by roughly ten percentage points. This places WordPress decisively at the bottom of the comparison. While the vast ecosystem of third-party themes and plugins is often cited as a factor in variable performance, the aggregate result indicates a systemic challenge for the platform.

These numbers have real-world implications. Platforms at the top of the list deliver faster, more responsive experiences to a greater proportion of their users. The nearly 40-percentage-point chasm between the top and bottom performers translates to millions of users encountering slower, less stable pages on the lower-ranked systems. For WordPress to improve its standing, a more proactive approach to performance within its ecosystem, such as establishing performance certifications for themes and plugins, could incentivize developers to prioritize speed and stability.

A persistent debate in the web development community centers on whether the choice of CMS directly influences search engine rankings. Some advocates point to WordPress’s flexibility and extensive SEO plugins as advantages. However, proprietary platforms like Duda, Wix, and Squarespace have heavily invested in baking sophisticated, automated SEO tools directly into their systems. While Core Web Vitals are confirmed as a ranking factor, most experts agree their direct impact on search position is relatively minor compared to content quality and relevance.

Nevertheless, performance remains critically important for immediate, measurable outcomes like user satisfaction and conversion rates. A slow site can deter a potential customer before they ever engage with the content. Therefore, the insights from the HTTPArchive report should not be dismissed. They provide a crucial benchmark for understanding which platforms are most effectively engineered for the modern web’s demand for speed and a seamless user experience.

(Source: Search Engine Journal)