At a glance the headline numbers for Preloaded fonts
How many fonts the page preloads.
The typical site preloads 0 fonts.
Distribution & median INP site count and median INP at each level of preloaded fonts
Passing INP by preloaded fonts which level passes the INP most often
Preloaded fonts 0. p75 0. p99 7. Spearman with INP r = +0.38. At the low end (0): INP 85ms. At the high end (>p98): INP 100ms. computed
Why this matters for the Core Web Vitals, and where to start fixing it
Fonts are discovered late by design. The browser must download the CSS, parse it, and find rendered text that actually uses an @font-face before it requests the font file. A preload skips that whole chain and starts the download with the HTML.
Preload the one or two fonts that render above-the-fold text, and stop there. Every preloaded font competes with the LCP image for early bandwidth. A preloaded font that is not used above the fold made the page slower for nothing.
How does this affect the Core Web Vitals?
Passing LCP barely moves across the range: 83% at one end, 80% at the other. 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.