The open benchmark for what consent banners actually cost.

We run every major consent banner under identical, fixed conditions and score it on banner speed, page impact, network cost and visitor experience. Open source, reproducible, and rerun as vendors change.

12 of 12 installations

Runs per integration: 20How scoring worksView test setup

Run 2026-09-23T13-16-00-056Z; fast desktop · cold cache · p75. Sorted by score, highest first. Each value is the p75 of 20 loads; intervals and every load are on the detail page.
#Provider0–100 against published anchors: Banner Speed 30%, Page Impact 25%, Network Cost 25%, Visitor Experience 20%. Good ≥ 80, Fair 60–79, Poor < 60.From navigation start until the consent banner was detected as visible.Bytes transferred beyond the no-SDK control on the same condition, read off the wire.Share of the first viewport the banner's bounding box occupied when detected.Largest Contentful Paint delay How much later the biggest element on screen, usually the main image or headline, renders than on the no-SDK control under the same condition. Reported, not scored.Cumulative Layout Shift added How much more content jumps around than on the no-SDK control under the same condition, for example when a banner pushes it down. 0 means the banner moved nothing. Reported, not scored.Total Blocking Time added How much longer scripts kept the browser too busy to respond to a tap or click than on the no-SDK control under the same condition, counting only the part of each long task past 50 ms. Scored in Page Impact.First Contentful Paint delay How much later the first text or image appears than on the no-SDK control under the same condition, so the site's own load time is taken out. Scored in Page Impact.
1CookieYes@cookieyes/nextjs@0.6.092Good451ms19.5KB11.7%521ms0.00025ms17ms
2CookieYes@cookieyes/react@0.8.091Good506ms22.7KB11.7%552ms0.00019ms95ms
3c15t@c15t/nextjs@2.2.1 (offline)81Good1.1s59.7KB27.8%117ms0.0004ms117ms
4c15t@c15t/react@2.2.1 (offline)80Good1.3s59.7KB27.8%180ms0.0005ms180ms
5CookieYesVendor CDN script79Fair1.9s28.3KB10.0%1.5s0.0004ms182ms
5EnzuzoVendor CDN script79Fair1.1s117.5KB9.4%671ms0.00061ms632ms
7OsanoVendor CDN script75Fair1.7s82.3KB12.8%415ms0.00046ms415ms
8IubendaVendor CDN script72Fair1.3s132.1KB23.5%397ms0.00052ms397ms
9c15t@c15t/react@2.2.169Fair2.9s59.7KB27.8%39ms0.0009ms39ms
10c15t@c15t/nextjs@2.2.168Fair3.0s59.8KB27.8%126ms0.0000ms126ms
11OneTrustVendor CDN script57Poor2.2s205.2KB16.4%735ms0.00236ms0ms
12KetchVendor CDN script49Poor3.3s353.0KB16.9%0ms0.000236ms0ms