Optimizely

Analytics

Optimizely loaded on 45 sites in our October 2026 scan: 2% of the 2,450 most-visited sites we checked, before any visitor had given consent.

Category: Analytics. A company can do several jobs; this is its main role on the pages we saw.

Its cookies typically last about 6 months. On 69% of the sites where it loaded, a consent banner was already present but hadn't been answered yet.

About Optimizely

Optimizely is an experimentation and A/B testing platform, the name the combined company took after Episerver acquired the original Optimizely in 2020.

Its cdn.optimizely.com script decides which version of a page or feature a visitor sees as part of a running experiment, and records which variant they got in a cookie such as optimizelyEndUserId so it stays consistent on later visits.

Often loaded alongside

Sites that load Optimizely most often also load Google Analytics (78%), Google (67%), Google Ads (67%), OneTrust (47%), and Adobe (27%).

Domains it loads from

cdn.optimizely.com
logx.optimizely.com
cdn3.optimizely.com
cdn-pci.optimizely.com
a4621041136.cdn.optimizely.com
a11179690159.cdn.optimizely.com
a20151573008.cdn.optimizely.com
a26669750187.cdn.optimizely.com
a2900460605.cdn.optimizely.com
a28007920049.cdn.optimizely.com
a25691410171.cdn.optimizely.com
a18132920325.cdn.optimizely.com
a10654255723.cdn.optimizely.com
a27224800026.cdn.optimizely.com
a25968344087.cdn.optimizely.com
a6558036.cdn.optimizely.com
rum.optimizely.com
tapi.optimizely.com
a27988430061.cdn.optimizely.com
prediction.cmab.optimizely.com
a25670000279.cdn.optimizely.com
a17586580222.cdn.optimizely.com
a17791710119.cdn.optimizely.com
a4894383279964160.cdn.optimizely.com
a19065870423.cdn.optimizely.com

Cookies

Sites that load Optimizely

The highest-ranked 30 of 45 sites.

cnn.com5 tracking companies
bbc.com4 tracking companies
slack.com6 tracking companies
klaviyo.com4 tracking companies
mixpanel.com2 tracking companies
prnewswire.com13 tracking companies
zoom.com3 tracking companies
jetbrains.com3 tracking companies
change.org6 tracking companies
kickstarter.com4 tracking companies

Show 20 more sites

fortune.com7 tracking companies
sky.com5 tracking companies
clevelandclinic.org7 tracking companies
techtarget.com4 tracking companies
asu.edu4 tracking companies
asana.com2 tracking companies
elastic.co2 tracking companies
inmotionhosting.com4 tracking companies
ford.com17 tracking companies
visa.com3 tracking companies
scmp.com17 tracking companies
parallels.com4 tracking companies
starbucks.com5 tracking companies
capitalone.com6 tracking companies
sonos.com5 tracking companies
heart.org5 tracking companies
ctvnews.ca38 tracking companies
unimelb.edu.au5 tracking companies
docusign.com9 tracking companies
infojobs.net8 tracking companies

Understanding this page

What the tracker categories mean
What "advertising," "analytics," "social," "consent" and the rest actually mean for a company or a cookie, and how CookieTosser decides which one applies.
First-party vs third-party cookies (and why "first-party" still tracks you)
What the distinction actually means technically, why browsers only block one of the two, and how CNAME cloaking, server-side tagging and cookies like _ga let sites keep tracking under their own domain.
How to block or limit trackers
Browser privacy settings, content blockers, Global Privacy Control and clearing cookies compared honestly — what each one actually stops, what it doesn't, and what it costs you in return.