What is the FPID cookie?
FPID is an HTTP cookie that Google Analytics (via the gtag.js script or Google Tag Manager loaded on a website) can create when a GA4 property uses a "first-party mode" setup — a method where Google issues identifiers from the visited site's own domain instead of a third-party Google domain.
The cookie is usually created on the visitor's first interaction with the page, as soon as the analytics script runs, and gets refreshed on later visits as long as the visitor returns before it expires.
What data it stores
FPID stores a unique, randomly generated identifier used to distinguish visitors from one another in Google Analytics reports. The exact value format is not documented in detail by Google and may differ from better-known cookies such as _ga.
The value is read by the Google Analytics script running on the site and sent to Google's servers (directly, or through a server-side container if the site uses one) for processing and aggregating traffic data.
What it is used for
The main purpose of FPID is to let Google Analytics recognize the same visitor across multiple visits and correctly calculate metrics such as unique users, sessions, and on-site behavior, even when the browser restricts classic third-party cookies.
For site owners, this cookie underpins traffic, acquisition-source, and user-behavior reports in the GA4 account, supporting marketing and content decisions.
Does it require consent?
CookieFix classifies FPID under the statistics (analytics) category. Since it is used for measuring and analyzing visitor behavior rather than being strictly necessary for the site to function, it falls under the ePrivacy Directive (transposed in Romania by Law 506/2004) and GDPR: it may only be set after the visitor's prior consent.
- Site owners must list FPID (and other Google Analytics cookies) in their cookie policy
- The GA/gtag script should only load after the visitor accepts the "statistics" category
- Rejecting consent must be as easy as accepting it, per ANSPDCP guidance
How to block or delete FPID
Visitors can delete or block FPID from their browser's cookie settings (Chrome, Firefox, Safari, Edge) or by using private browsing; some browsers with built-in anti-tracking protection may automatically limit how long this type of cookie persists.
For site owners, blocking it correctly before consent means using a CMP that stops the Google Analytics script from running until the "statistics" category is accepted — CookieFix, for example, can automatically block such scripts and only activate them after consent.
Frequently asked questions
It's an HTTP cookie set by Google Analytics to identify site visitors on a first-party basis, as an alternative to third-party cookies increasingly blocked by modern browsers.
It typically lasts 2 years from being set or last renewed, if the visitor returns to the site.
Yes, since it's used for analytics purposes, setting it requires prior consent under GDPR and the ePrivacy Directive.
Visitors can remove it from their browser's cookie settings, and site owners can automatically block it until consent is given using a CMP like CookieFix.