Website Performance Statistics: Speed and Page Weight

What the numbers say

The web is getting faster in one important measure, while its pages keep growing. In the 2025 Web Almanac performance analysis, 48% of mobile sites had good Core Web Vitals, up from 32% in 2021. Desktop reached 56% in 2025. These are shares of observed sites with field-data coverage, not a promise that every visitor had a fast experience.

The other side of the story is weight. The Page Weight chapter puts the median mobile home page at 2,559 KB in July 2025. Images accounted for 911 KB. Removing every image will not automatically make a site fast: network conditions, JavaScript work, server response, and layout behavior matter too. It does tell a team where to inspect first when an image-heavy page feels slow.

How to use these figures

Use the Core Web Vitals trend to explain the state of the web, then measure your own visitors before choosing fixes. The Almanac combines the HTTP Archive crawl with Chrome UX Report field data. Its methodology explains the July 2025 crawl and why field-data coverage is not identical to the full crawl population. The trend does not establish that one design practice caused the improvement.

For a new site, write a performance budget before launch. Set an image-size target, test the main templates on a mid-range phone, and check real-user Core Web Vitals once traffic allows it. Start with the pages that lead to a contact request or sale. A fast homepage will not rescue a slow checkout.

The 48% mobile versus 56% desktop gap is a planning reminder. Review on the devices your audience uses. Desktop lab tests alone miss much of the mobile experience.

Limits and related reading

These figures are cross-site benchmarks. They do not measure Online Marketing HQ clients, prove a conversion lift from a faster page, or establish a universal target of 2,559 KB. The page-weight figure is a median observed size, not a recommendation. Consult the original performance chapter for definitions and the underlying charts before quoting a comparison.

For practical next steps, read our guide to planning a first website, SEO foundations for new websites, and website building topic hub.