You are here: Tags / fpid
The FPID cookie is what server-side Google Tag Manager would prefer to use for your Google Analytics 4 tracking. It’s a cookie set in the HTTP response from the server, and it’s flagged as HttpOnly, which means it’s only accessible by a web server running on the domain on which it was set. There’s nothing wrong with the technology, and I do recommend that server-side setups toggle it on by default.

Continue reading

The FPID cookie in server-side tagging for Google Tag Manager is an HttpOnly, server-managed ID cookie that’s designed to replace the JavaScript-managed _ga cookie used by Google Analytics 4 and Universal Analytics. For more details about the cookie itself, check out my previous article on FPID. In that article, I mentioned one caveat for adopting FPID being the fact that cross-domain tracking will not work. I mean, how could it? FPID is an HttpOnly cookie, which means it’s not available to JavaScript in the browser.

Continue reading

Author's picture

Simo Ahava

Husband | Father | Analytics developer
simo (at)

Senior Data Advocate at Reaktor