How to find actual size of data in a table

Does anyone know how to determine the actual szie of a table in oracle. Not the extent size, but the actual amount of that used by data. The logical table size is easy to get, but if I delete data from a table after an extent has been added, then I still get the max size as opposed to the actual size. I need this because I need to then copy that data to a remote database (long story), and I need to be sure that a) the table will fit in available space, and that b) space is not wasted (as would be if using the size value corresponding to that max size) Thanks (please respond to my email address as well as the newsgroup since I seem to be having intermittent trouble accesseing the newsgroups..)

Ati

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