What is the WMF-Uniq cookie?
A short-lived, randomly generated cookie the Wikimedia Foundation uses to sample and de-duplicate pageviews on Wikipedia and its sister sites, without identifying the visitor long-term.
Our October 2026 scan found it on 11 sites (0% of the 2,450 we scanned), set before any consent.
- Purpose
- Analytics
- Belongs to
- Wikimedia
- Set as
- First-party on 73% of sites, third-party on 27%
- Typical lifetime
- 12 months
Sites that set WMF-Uniq before consent
The highest-ranked 11 of 11 sites.
- wikipedia.org0 tracking companies
- wikimedia.org0 tracking companies
- goal.com0 tracking companies
- wiktionary.org0 tracking companies
- testbook.com6 tracking companies
- wikisource.org0 tracking companies
- wikibooks.org0 tracking companies
- mediawiki.org0 tracking companies
- wikidata.org0 tracking companies
- admissions.nic.in1 tracking company
Show 1 more site
- wikiquote.org0 tracking companies
Related cookies
Other cookies from Wikimedia.
- GeoIP8 sites
- NetworkProbeLimit8 sites
- WMF-Last-Access8 sites
- WMF-Last-Access-Global8 sites
How to stop it
Declining non-essential cookies in a site's consent banner should stop WMF-Uniq being set on later visits. Blocking third-party cookies in your browser settings stops the third-party kind everywhere, and clearing cookies for a site removes any it already set.
Description written by CookieTosser, for a cookie the Open Cookie Database doesn't cover.
Understanding this page
- How cookie lifetimes work, and why a 13-month _ga matters
What a cookie's "expires" field actually controls, why Google Analytics ships a 2-year default that many sites cut down to 13 months, and how Safari's 7-day cap on script-set cookies changes the picture.
- 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.