The State of Web Vitals

Web font formats on React sites

96.9% of font-using sites (9,139) serve modern WOFF2 fonts and reach 85% good LCP (1.4s median), while the 14.0% still serving legacy WOFF (66% good LCP) and 7.3% serving uncompressed TTF (60% good LCP) lag behind.

Field data PhoneDesktopAll Scope All sites October 2026 edition · Phone field outcomes · React sites only
React Scoped to 9,570 sites out of 210,902 analyzed (frameworks) Compare with all sites →

96.9% of React sites use WOFF2 fonts web font format, and 85% of those sites have a good LCP, against 84% of all React sites.

The State of Web Vitals · October 2026 · React: 9,570 crawled sites · 5,488 with phone field data · 9,431 sites with web font formatBy Arjen Karel · corewebvitals.io/state-of-cwv
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LCP pass rate

Sites with WOFF2 fonts web font format have a good LCP most often: 85%, against 84% of all React sites. Sites with TrueType (TTF) fonts font formats have it least often, at 60%.

SitesGood, needs improvement, poor LCPMedian
All React sites5,48884%1.4s
WOFF2 (Brotli-compressed) 96.9%5,21985%1.4s
OpenType (OTF) 1.5%9067%2.0s
WOFF (Legacy zlib) 14.0%78366%2.1s
Other font formats 0.8%5564%2.2s
TrueType (TTF) 7.3%43160%2.2s
GoodNeeds improvementPoorSites: with Chrome field data
The State of Web Vitals · October 2026 · React: 9,570 crawled sites · 5,488 with phone field data · 9,431 sites with web font formatBy Arjen Karel · corewebvitals.io/state-of-cwv
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Web font format usage

WOFF2 fonts is the most used: 96.9% of React sites.

Sites using each option (sites can use more than one) 9,431 sites
WOFF2 (Brotli-compressed) 96.9% WOFF (Legacy zlib) 14.0%
WOFF2 (Brotli-compressed) 96.9% WOFF (Legacy zlib) 14.0% TrueType (TTF) 7.3% OpenType (OTF) 1.5% Other font formats 0.8%
The State of Web Vitals · October 2026 · React: 9,570 crawled sites · 5,488 with phone field data · 9,431 sites with web font formatBy Arjen Karel · corewebvitals.io/state-of-cwv
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LCP phase breakdown by web font format

Across the four LCP sub-parts in Chrome's field data, the largest gap between WOFF2 fonts and TrueType (TTF) fonts sits in time to first byte (TTFB): 490 ms median for WOFF2 fonts against 1181 ms for TrueType (TTF) fonts. Overall median field LCP is 1.4s for WOFF2 fonts (TTFB 490 ms, load delay 438 ms, load duration 131 ms, render delay 178 ms) versus 2.3s for TrueType (TTF) fonts.

Median LCP phase breakdown (Chrome field p75) Load delay Median LCP
React sites with web font format 4,124502 ms433 ms433 mslab 439 ms1.4s
TrueType (TTF) 3441181 ms372 ms325 ms372 mslab 376 ms2.3s
OpenType (OTF) 721186 ms386 ms260 ms386 mslab 375 ms2.0s
WOFF2 (Brotli-compressed) 3,974490 ms438 ms438 mslab 445 ms1.4s
WOFF (Legacy zlib) 621975 ms470 ms254 ms470 mslab 459 ms2.1s
Other font formats 48814 ms700 ms260 ms700 mslab 676 ms2.2s
TTFB Resource load delay Resource load time Element render delay
The State of Web Vitals · October 2026 · React: 9,570 crawled sites · 5,488 with phone field data · 9,431 sites with web font formatBy Arjen Karel · corewebvitals.io/state-of-cwv
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Web font format per platform

Wix sets the web font format to WOFF2 fonts on 100% of its sites, and 94% of Wix sites have a good LCP, against 84% of all sites.

PlatformWeb font format on its sitesGood LCP
React sites with web font format 9,431 sitesWOFF2 (Brotli-compressed) 97%WOFF (Legacy zlib) 14%84%
Wix 5,801 sitesWOFF2 (Brotli-compressed) 100%94%
WordPress 2,305 sitesWOFF2 (Brotli-compressed) 93%WOFF (Legacy zlib) 42%TrueType (TTF) 21%63%
WOFF2 (Brotli-compressed) WOFF (Legacy zlib) TrueType (TTF) OpenType (OTF) Other font formats
The State of Web Vitals · October 2026 · React: 9,570 crawled sites · 5,488 with phone field data · 9,431 sites with web font formatBy Arjen Karel · corewebvitals.io/state-of-cwv
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Web font format or the platform

Does the platform explain the web font format difference?

On Wix, 94% of sites with WOFF2 fonts web font format have a good LCP, against 94% of Wix sites with legacy WOFF fonts. Within Wix, sites with WOFF2 fonts and legacy WOFF fonts have a good LCP about equally often. On WordPress, 62% of sites with WOFF2 fonts web font format have a good LCP, against 61% of WordPress sites with legacy WOFF fonts. Within WordPress, sites with WOFF2 fonts and legacy WOFF fonts have a good LCP about equally often.

Why WOFF2 replaces legacy WOFF, TTF, and OTF across all modern browsers

WOFF2 uses custom Brotli preprocessing to compress font glyphs ~30% smaller than legacy WOFF and up to 50%+ smaller than raw TTF or OTF files, and has been supported by every major browser since 2016. Across 9,139 font-using sites (96.9%) serving WOFF2, good LCP reaches 85% (1.4s median). Sites still serving legacy WOFF (14.0%, 1,320) drop to 66% good LCP (2.1s median), and sites serving raw TTF (7.3%, 690) drop to 60% good LCP (2.2s median).

The State of Web Vitals · October 2026 · React: 9,570 crawled sites · 5,488 with phone field data · 9,431 sites with web font formatBy Arjen Karel · corewebvitals.io/state-of-cwv
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Understanding web font formats

Declare only format("woff2") in your @font-face src rules and ensure WOFF2 is listed first if legacy fallbacks exist, so modern browsers never download uncompressed TTF or WOFF files. Across all font-using sites, 96.9% serve WOFF2 (85% good LCP) versus 7.3% serving raw TTF (60% good LCP).

Go fix it Self-host Google Fonts → Responsive font loading strategy →
The State of Web Vitals · October 2026 · React: 9,570 crawled sites · 5,488 with phone field data · 9,431 sites with web font formatBy Arjen Karel · corewebvitals.io/state-of-cwv
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