WordPress runs more of the web than every other CMS combined, and passes Google's Core Web Vitals on mobile just 38.4% of the time, the lowest of any major platform. The reason is loading, not responsiveness.
Key Findings
- 1.Among the major general-purpose CMS platforms, WordPress has the lowest mobile pass rate at 38.4%. Every other major platform beats it: Duda 60.7%, Drupal 54.9%, Webflow 54.4%, Wix 53.0%, Squarespace 52.6%, Joomla 42.1%.
- 2.WordPress is also by far the biggest, accounting for 2.98 million of the sites measured, more than fourteen times the next platform. The most-used CMS is also the slowest-passing.
- 3.The problem is loading, not responsiveness. WordPress passes INP on 93.8% of sites and CLS on 91.5%. Only 59.2% have good loading (LCP), and that one metric caps the whole platform.
- 4.The hosted builders lead on loading: Duda 95.1% good-LCP, Wix 86.1%, Squarespace 80.1%, all clearing WordPress's 59.2% comfortably.
- 5.Responsiveness is nearly universal. Every major CMS clears 89% good-INP on mobile. The CMS you choose barely affects responsiveness. It strongly affects loading.
Summary
The platform you build your website on decides a surprising amount about how fast it feels to real visitors, and the most popular choice is the slowest-passing. Across 3.7 million sites, WordPress passes Google's Core Web Vitals on mobile just 38.4% of the time, the lowest rate of any major general-purpose CMS. Every other platform beats it: Duda passes 60.7% of the time, Drupal 54.9%, Webflow 54.4%, Wix 53.0%, Squarespace 52.6%, even Joomla 42.1%. The tool that runs more of the web than every rival combined is the one least likely to clear Google's performance bar.
That gap has real consequences, because speed drives the outcomes a site exists for. Slow pages lose visitors before they convert, depress the sales, sign-ups, and reads a site is built to produce, and rank lower in search, since Google treats loading, responsiveness, and stability as ranking signals. Choosing a platform is therefore also choosing a default level of performance, and for millions of owners that default is working against them without their knowing it.
These numbers come from HTTP Archive technology detection, which identifies the CMS behind each site, joined to Google's Chrome User Experience Report, the real-user field data collected from the Chrome browsers of actual visitors, the same signals Google's ranking systems use. That pairing lets us compare platforms at population scale rather than by testing a handful of showcase sites.
What the data covers
The benchmark spans 3.7 million websites across the major general-purpose CMS platforms, measured on mobile at the 75th percentile against Google's Core Web Vitals thresholds. Commerce platforms such as Shopify and WooCommerce are excluded and covered separately. Passing means clearing all three metrics at once: good loading (Largest Contentful Paint under 2.5 seconds), good responsiveness (Interaction to Next Paint under 200 milliseconds), and good visual stability (Cumulative Layout Shift under 0.1), for the three-quarters of real visitors who define the typical experience.
The most popular CMS is the slowest-passing
WordPress runs more sites than any other CMS by a wide margin, 2.98 million of the sites in our sample against 207,000 for Wix, the next largest, more than fourteen times the runner-up. Across those millions of sites it passes Core Web Vitals on mobile just 38.4% of the time, the lowest pass rate of any major general-purpose CMS we measured.
The ranking above WordPress is led by the hosted builders. Duda passes 60.7% of the time and Drupal, Webflow, Wix, and Squarespace all cluster in the low-to-mid 50s. The single most popular way to build a website is also the one least likely to pass Google's performance bar, which means the platform decision sets the performance ceiling for a huge share of the web.
Source: PageSpeed Matters analysis of 3.7 million sites with CrUX field data, June 2026.
The single most popular way to build a website is the one least likely to pass Google's performance bar.
Loading is the whole problem
WordPress is not failing on responsiveness or visual stability. It passes INP, the responsiveness metric, on 93.8% of sites, and CLS, the visual-stability metric, on 91.5%. Both are healthy. What drags it down is loading: only 59.2% of WordPress sites have good Largest Contentful Paint on mobile, and because a site has to pass all three metrics, that one weak number caps the whole platform.
The hosted builders lead on exactly this metric. Duda posts 95.1% good LCP, Wix 86.1%, Squarespace 80.1%, all clearing WordPress's 59.2% comfortably, because they control the whole rendering pipeline and make fast loading the default rather than the reward for tuning. Responsiveness, by contrast, is nearly universal: every major CMS clears 89% good INP on mobile. The CMS you choose barely affects responsiveness. It strongly affects loading.
| CMS | Mobile sites | Mobile pass | Good LCP | Good INP | Good CLS |
|---|---|---|---|---|---|
| Duda | 47,462 | 60.7% | 95.1% | 96.4% | 94.6% |
| Drupal | 99,447 | 54.9% | 78.1% | 92.3% | 92.3% |
| Webflow | 64,651 | 54.4% | 77.7% | 92.2% | 95.2% |
| Wix | 207,227 | 53.0% | 86.1% | 93.8% | 98.0% |
| Squarespace | 99,635 | 52.6% | 80.1% | 97.8% | 93.0% |
| Joomla | 99,574 | 42.1% | 72.7% | 89.8% | 91.0% |
| WordPress | 2,984,893 | 38.4% | 59.2% | 93.8% | 91.5% |
Commerce platforms (Shopify, WooCommerce) are excluded and covered separately.
Source: PageSpeed Matters analysis, mobile 75th-percentile field data, June 2026.
The hosted builders control the whole rendering pipeline, so fast loading is the default rather than the reward for tuning.
The loading ceiling is the whole story
None of this is a verdict on WordPress as software. It is a verdict on the average WordPress site, which passes on mobile just 38.4% of the time even though its responsiveness (93.8% good INP) and stability (91.5% good CLS) are already healthy. Loading is the single metric holding it back: only 59.2% of WordPress sites have good LCP. If you run WordPress and want to pass, aim at loading and largely leave the rest alone, since it is already fine, and our ultimate WordPress speed guide walks through the loading fixes step by step.
If you are still choosing a platform rather than tuning one you already run, that same loading number is the decision. Duda reaches 95.1% good LCP and Wix 86.1%, against WordPress's 59.2%, because the hosted builders own the whole rendering pipeline and make fast loading the default instead of the reward for tuning. The WordPress vs Webflow vs Squarespace speed comparison is the companion buyer's read. The platform sets the loading ceiling across all 2.98 million WordPress sites in this sample, and the owner decides where beneath it a given site actually lands.