HTTP Archive 2025 Web Almanac Reveals a Decade of Growth, Persistent Accessibility Gaps, and Shifting CSS Adoption

The annual HTTP Archive Web Almanac is more than just a report; it's the most comprehensive snapshot of the live web we have. This year's edition, analyzing 17.2 million websites, confirms what many developers feel in their day-to-day work: the web is getting heavier, more complex, and while some areas are improving, fundamental accessibility and performance practices are still lagging far behind. The report is a 15-chapter deep dive, but a few key findings from the CSS, Performance, and Accessibility chapters stand out as critical indicators for frontend architects and designers.

The Lost Decade of Page Weight

One of the most staggering statistics in the report is the growth in page weight over the last ten years. In July 2015, the median mobile home page weighed a relatively modest 845 KB. By July 2025, that same median page had ballooned to 2,362 KB—a 202.8% increase. This isn't just a slow creep; it's a fundamental shift in how we build for the web.

JavaScript is a primary contributor, with the median mobile page now shipping 697 KB of it. While images remain the heaviest asset class, the sheer volume of JavaScript is a significant performance burden, especially on mid-range mobile devices and slower networks. This growth underscores a critical tension in modern web development: the drive for rich, interactive experiences often comes at the direct expense of performance and accessibility. For teams focused on Core Web Vitals, this data is a stark reminder that the baseline for "fast" is moving in the wrong direction for the median site.

CSS: Modern Features Gain Traction, But Adoption is Uneven

The CSS chapter offers a more optimistic, if nuanced, view. The adoption of variable fonts has moved from novelty to norm. This year's data shows that 39.4% of desktop sites and 41.3% of mobile sites use at least one variable font. This is a significant milestone, indicating that the benefits of single-file font loading, design flexibility, and performance are being recognized at scale. For designers and developers, this means variable fonts are no longer an experimental consideration but a standard tool in the kit.

Newer CSS properties are also making their debut, albeit slowly. The text-wrap property, which shipped in 2023, is seeing early adoption with the balance value appearing on 2.67% of sites and pretty on 1.71%. While these are small percentages, they signal that developers are beginning to tackle nuanced typography challenges directly in CSS, moving away from JavaScript-based solutions for text layout. This is a positive trend for both performance and design integrity.

However, the report also highlights a persistent problem: the CMS landscape remains dominated by WordPress. The finding that WordPress's growth is stabilizing suggests a maturation of the platform, but it also means that the vast majority of the web is built on a system where advanced CSS features may not be easily accessible without custom development. This creates a divide between bespoke, modern sites and the long tail of the web that relies on template-driven CMS platforms.

Accessibility: A Persistent and Widespread Failure

Perhaps the most concerning findings are in the Accessibility chapter. Despite years of advocacy and clear guidelines, the web remains largely inaccessible to users who rely on keyboard navigation or screen readers.

The most egregious failure is the removal of focus styles. A staggering 67% of sites remove focus outlines, directly violating WCAG requirement 2.4.7 (Focus Visible). This practice, often done to achieve a cleaner visual aesthetic, actively harms keyboard users by making navigation impossible. It's a stark example of prioritizing visual design over fundamental usability.

Color contrast is another chronic issue. Only 30% of sites meet WCAG color contrast guidelines. While this is an improvement from 21% in 2020, it means that 70% of sites still present readability challenges for users with visual impairments. This is a solvable problem with modern tools and testing, yet it persists at scale.

The report also notes that 44% of sites are failing to provide meaningful alternative text for images. This is calculated from 30% of sites using empty alt attributes (suggesting decorative images) and 14% omitting the attribute entirely. While some images are indeed decorative, the high percentage suggests many sites are not considering the experience of users who cannot see the visual content.

The ARIA Paradox

Interestingly, ARIA (Accessible Rich Internet Applications) usage is high, with 70% of pages using ARIA attributes and 29% on buttons. However, the report rightly cautions that this doesn't equate to better accessibility. ARIA can be a powerful tool when used correctly, but it can also introduce new barriers if applied incorrectly. This high usage rate likely reflects the complexity of modern web apps, but it also indicates that many developers are reaching for ARIA as a quick fix rather than building with semantic HTML first. The lesson here is that ARIA is a supplement, not a substitute, for proper HTML structure.

What This Means for the Web's Future

The 2025 Almanac paints a picture of a web at a crossroads. On one hand, we have powerful new tools like variable fonts and advanced CSS properties that can create better, more performant experiences. On the other hand, the foundational practices of accessibility and performance are being neglected at scale, leading to a heavier, less inclusive web.

For frontend architects and teams, the takeaway is clear: the data provides a mandate to prioritize. The growth in page weight is unsustainable, and the accessibility failures are ethically and legally untenable. While new CSS features are exciting, the real work lies in applying them thoughtfully while also addressing the core issues of performance, accessibility, and semantic markup that affect every user, every day. The full HTTP Archive Web Almanac 2025 is an essential read for anyone who cares about the health and future of the web platform.