How do I clean up unused objects

I got so many unused objects in my game. Is there any way to clean it up?

Is there any easy yet effective method to do it, instead of checking if it is used on every layout.

As an option to create a separate layout and all the game objects in the editor to add to it. Already at the start of other layout prescribe establishment of the necessary facilities in the desired position. Since unused objects will not hang in the memory.

Thanks DeXVinogradov,

When I export the game, all of the objects are included on the game file, right?

That makes its size enormous. How to prevent that?

Probably not the objects per se that are the problem - do you have very big sound and music ? very hi res graphics ? The actual code part is not likely to be too large.