Hi Dan
There is no specification limit. If you look in HELP for "specification" limit
you will find.
Sheets in a workbook
Limited by available memory (default is 3 sheets)
Tom Ogilvy once created a test workbook with a few thousand sheets
and terminated macro before completion. Whether you can put much
in those sheets is another matter but again not a specification limit but
limitations on memory.
Keep in mind that Excel does not make a very efficient data base.