What is the __pnahc cookie?
This cookie stores the result of previous Adblock detection, removes false-positive AdBlock detection clauses.
Our October 2026 scan found it on 9 sites (0% of the 2,450 we scanned), set before any consent.
- Purpose
- Functional
- Belongs to
- Piano
- Set as
- First-party (under the site's own domain)
- Typical lifetime
- 3 months (vendor says: 90 days) — about what the vendor documents
Sites that set __pnahc before consent
The highest-ranked 9 of 9 sites.
- onet.pl6 tracking companies
- jutarnji.hr10 tracking companies
- scmp.com17 tracking companies
- thehindu.com7 tracking companies
- tagesspiegel.de1 tracking company
- mainichi.jp30 tracking companies
- japantimes.co.jp32 tracking companies
- foreignpolicy.com22 tracking companies
- washingtontimes.com21 tracking companies
Related cookies
Other cookies from Piano.
How to stop it
Declining non-essential cookies in a site's consent banner should stop __pnahc 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 from the Open Cookie Database (Apache 2.0).
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.