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 79% good LCP (1.5s median), while the 14.0% still serving legacy WOFF (68% good LCP) and 7.3% serving uncompressed TTF (61% good LCP) lag behind.

Field data PhoneDesktopAll Scope All sites October 2026 edition · Desktop 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 79% of those sites have a good LCP, against 79% of all React sites.

The State of Web Vitals · October 2026 · React: 9,570 crawled sites · 1,979 with desktop 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: 79%, against 79% of all React sites. Sites with TrueType (TTF) fonts font formats have it least often, at 61%.

SitesGood, needs improvement, poor LCPMedian
All React sites1,97979%1.5s
WOFF2 (Brotli-compressed) 96.9%1,85279%1.5s
OpenType (OTF) 1.5%5474%1.8s
WOFF (Legacy zlib) 14.0%42268%1.9s
Other font formats 0.8%2767%1.7s
TrueType (TTF) 7.3%23361%2.1s
GoodNeeds improvementPoorSites: with Chrome field data
The State of Web Vitals · October 2026 · React: 9,570 crawled sites · 1,979 with desktop 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 · 1,979 with desktop 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): 720 ms median for WOFF2 fonts against 1212 ms for TrueType (TTF) fonts. Overall median field LCP is 1.6s for WOFF2 fonts (TTFB 720 ms, load delay 417 ms, load duration 146 ms, render delay 192 ms) versus 2.1s for TrueType (TTF) fonts.

Median LCP phase breakdown (Chrome field p75) Load delay Median LCP
React sites with web font format 1,295712 ms413 ms413 mslab 429 ms1.6s
OpenType (OTF) 41660 ms327 ms327 mslab 380 ms1.7s
TrueType (TTF) 1911212 ms360 ms277 ms360 mslab 412 ms2.1s
WOFF (Legacy zlib) 3091011 ms399 ms246 ms399 mslab 440 ms2.0s
WOFF2 (Brotli-compressed) 1,232720 ms417 ms417 mslab 431 ms1.6s
TTFB Resource load delay Resource load time Element render delay
The State of Web Vitals · October 2026 · React: 9,570 crawled sites · 1,979 with desktop 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 92% of Wix sites have a good LCP, against 79% 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%79%
Wix 5,801 sitesWOFF2 (Brotli-compressed) 100%92%
WordPress 2,305 sitesWOFF2 (Brotli-compressed) 93%WOFF (Legacy zlib) 42%TrueType (TTF) 21%66%
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 · 1,979 with desktop 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 WordPress, 66% of sites with WOFF2 fonts web font format have a good LCP, against 63% 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 79% (1.5s median). Sites still serving legacy WOFF (14.0%, 1,320) drop to 68% good LCP (1.9s median), and sites serving raw TTF (7.3%, 690) drop to 61% good LCP (2.1s median).

The State of Web Vitals · October 2026 · React: 9,570 crawled sites · 1,979 with desktop 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 (79% good LCP) versus 7.3% serving raw TTF (61% 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 · 1,979 with desktop field data · 9,431 sites with web font formatBy Arjen Karel · corewebvitals.io/state-of-cwv
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