Compressing Folders

I have a directory that contain date partitions and at the end of the day a compression analytic is ran to compress these date folders.

Sometimes the size of the folders are not the expected size if the compression was successful so I want to find out for sure have the folders been compression or not. I have seen some commands regarding individual files but not folders.

Thanks

Can you be more clear? Partitions are not directories.... What do you call folders?
Not knowing what utility/ies you use for your task it will be difficult to give you an answer

Then we need to know more about your system: UNIX/linux what version and what shell you use
We need more information on what your data looks like when normal and when "not expected" like what kind of content and size...