You are not going to believe it vs You won't believe it.

English as a Second Language English Vocabulary, Grammar and Idioms
1

Hello,
If I am about to tell some news, and I know that the people I am talking to will be greatly surprised, which one is correct - You are not going to believe it or You won’t believe it.

Thank you in advance

2

I would use ’ You won’t believe this/ it’.
I perefer to use ’ tobe +going to ’ to perdict the future when I can realize it becasuse of the situation now.
_ The sky is cloudy, tonight is going to be warmer than last night.

3

You can use either, Vectra.