Total Blocking Time (TBT) and the Core Web Vitals
39.3% of audited sites (81,161) record 0ms of lab Total Blocking Time (95% good field INP, 81ms median) and 34.8% stay within 1 to 200ms (96% good INP), while the 12.7% exceeding 600ms TBT drop to 93% good INP (95ms median).
Two in five sites, 39.3%, have no lab Total Blocking Time (TBT). Of the 60.7% that do, 57% use 1 to 200ms TBT, and 96% of those sites have a good INP, against 95% of all sites.
INP pass rate
Sites with 1 to 200ms TBT lab Total Blocking Time (TBT) have a good INP most often: 96%, against 95% of all sites. Sites with over 600ms TBT Total Blocking Time have it least often, at 93%.
Lab Total Blocking Time (TBT) usage
Three in five sites uses lab Total Blocking Time (TBT), and 57% of those use 1 to 200ms TBT.
Understanding Total Blocking Time (TBT)
How lab Total Blocking Time translates into field INP responsiveness
Total Blocking Time sums the blocking portion (anything past 50ms) of every long main-thread task during lab page load. Across 81,161 sites (39.3%) with 0ms TBT and 71,727 sites (34.8%) within 1 to 200ms TBT, 95% and 96% pass field INP (81ms and 87ms median). When lab TBT rises to 201 to 600ms (13.1%), good INP dips to 95% (92ms median), and past 600ms TBT (12.7%, 26,262 sites) good INP falls to 93% (95ms median).
Keep lab Total Blocking Time under 200ms by code-splitting large bundles, deferring non-critical third-party tags until after first interaction, and yielding to the main thread via scheduler.yield() between startup tasks. Across all audited sites, 34.8% sit at 1 to 200ms TBT (96% good INP) while 12.7% exceed 600ms (93% good INP).
How lab Total Blocking Time (TBT) plays out per platform
What the field data shows when you isolate a single CMS or framework.
WordPress 65,509 sites 17.5% of WordPress sites exceed 600ms lab TBT (97% good field INP vs 98% at 1 to 200ms TBT).
Across 65,509 WordPress sites, 29.6% record 0ms lab TBT (98% good INP), 36.9% sit at 1 to 200ms TBT (98% good INP), and 17.5% exceed 600ms TBT (97% good INP, 94ms median).
Shopify 8,573 stores 20.2% of Shopify stores exceed 600ms lab TBT (90% good INP vs 98% at 0ms TBT, 8 points apart).
Across Shopify storefronts, 26.0% record 0ms lab TBT (98% good field INP), 36.3% record 1 to 200ms TBT (98% good INP), and 20.2% exceed 600ms TBT (90% good INP, 118ms median).
React & Next.js 9,570 sites React & Next.js sites over 600ms lab TBT (13.7%) pass field INP at 93% vs 97% at 0ms TBT.
Across React sites, 31.2% record 0ms lab TBT (97% good INP), 14.3% sit at 201 to 600ms TBT (93% good INP), and 13.7% exceed 600ms TBT (93% good INP).
Wix 5,825 sites 81% of Wix sites sit at or below 200ms TBT (98% good INP at 0ms vs 94% over 600ms).
Across 5,825 Wix sites, 36.7% record 0ms lab TBT (98% good INP), 44.2% record 1 to 200ms TBT (98% good INP), and 8.2% exceed 600ms TBT (94% good INP).
By Arjen Karel · 210,902 crawled sites (196,263 with all devices Chrome field data, 206,258 sites with lab Total Blocking Time (TBT), October 2026). How we measured.