There will be as many people as will come.

[JACEK1]

Hello everybody!

There will be as many people as will come.

Suppose that there is a dialogue between two people:

A: Have you invited all your guests yet?

B: No, not yet. Besides, there will be as many people as will come.

For instance, 12 people will come, so there will be 12 people.

Do you accept the sentence in bold type?

[emsr2d2]

There is no sentence in bold (and you forgot the question mark at the end).

[JACEK1]

I have made the corrections.

[emsr2d2]

I don't understand what it's supposed to mean. Are you saying that you don't know exactly how many people will come but you are going to invite 12 people?

[GoesStation]

I'd say something like Whoever comes, comes. It's a casual way to say I'm not concerned about how many people show up.

[JACEK1]

No. Let's start again.

There will be a different dialogue.

A) How many people do you expect to come to the party tomorrow?
B) There will be as many people as will come.

Person B does not know how many people will arrive.

[emsr2d2]

B's sentence is not natural. GoesStation's suggestion was a good one to mean what you are trying to say. The simplest answer, of course, is "I don't know" or "I've [got] no idea".