Fbp parameter in Facebook Conversion API GTM Tag Template

Hi, my main issue is that I get different fbp parameter in outgoing HTTP request from server-side GTM to graph.facebook. Maybe there’s something I don’t understand, but I don’t have any more idea.

Below is the testing setup, which is pretty basic (as default as it can be), but I’m getting different fbp values for every page view. Since I’m a new user here (I can embed just one media) it’s all shown as one image.

So, the whole setup seems pretty basic, I don’t see any issues.

Consecutive 3 page views that are being sent from wGTM to sGTM trigger outgoing POST request to https://graph.facebook.com/v14.0/123456789012345/events?access_token=defz6z56zz45tz54454g4ghrth56j5 (I know, FB pixel ID and request token are not correct, that’s why the call itself fails) where the fbp parameter has 3 different values (1 for each pageview):




I guess the only thing that could cause this is wrong pixel id and/or request token?

Because everything else seems OK to me.

Does anyone maybe have a more specific explanation the options below are used for? Maybe I’m misunderstanding them …

  • Generate _fbp cookie if it not exist
  • Use HttpOnly cookies


Edit: some typos

Hello, do you use a custom domain for your sGTM? Looks like this is the reason why you get random fbp.

Hey, I’m not using a custom domain yet. Currently I’m using the domain that Google cloud provides for the App engine.

And it looks to me that the only thing that’s left for me to try is to use a custom domain - subdomain of the main domain that’s sending data from wGTM to sGTM.

I was planning to use this anyway but zdravo was eager to test the whole setup so it looks I might got ahead of myself :grin:

Hopefully it will work then. Otherwise I won’t have a clue what to do.

yes, test with a custom domain. Because with the default Google cloud domain sGTM tag can’t set cookies accurately because it’s not under your main site domain.