Facebook Custom Audiences approximate_count value is too low

Question

I finished uploading users into audiences and everything went smoothly, no error received. I checked the audiences and approximate_count shows only a small fraction of the number of uploaded users.

How is it possible? How is this number calculated?

Thanks for the help!

Answer 1

From what I know and from the documentation isn't really possible at the moment.

Which logic stands behind is obscure to me and, frankly, uncomprehensible that one can only obtain an "aproximate" number of users in an audience.

You should apply you own logic and data keeping beyond that.