At a glance the headline numbers for HTML compression
Compression on the HTML document: brotli, gzip, or none.
28.5% of HTML documents are Brotli-compressed. 19.4% ship raw.
HTML compression who uses what, and how fast each group loads
Little daylight between the groups: every variant sits near 47ms median INP. computed
Passing INP per HTML compression which group passes the INP most often
No variant stands out: pass rates sit between 99% and 99%. computed
Why this matters for the Core Web Vitals, and where to start fixing it
The HTML document is the first thing the browser reads, and the sooner the markup arrives, the sooner the preload scanner can discover everything else: the stylesheets, the fonts, the LCP image. Brotli and gzip shrink HTML to a fraction of its raw size. None means the visitor downloads every byte of markup before the page can even start discovering resources.
Brotli compresses tighter than gzip and every major CDN offers it. This is a switch, not a project.
How does this affect the Core Web Vitals?
The choice barely moves the LCP: 88% pass at best, 84% at worst. This signal does not separate passing sites from failing ones.
Chrome field data from 94,910 sites, representing millions of real page loads. How we measured.