A used range in an Excel worksheet is a concept that defines which cells in a worksheet have been used. In any given worksheet, the current used range can impact how many cells are involved in certain calculations. To find the last cell used in a worksheet (the lower right corner of the used range) you can use keyboard shortcuts:

  1. Go to the first cell in the worksheet (Ctrl + Home)
  2. Go to the last cell (Ctrl + End)

The used range is continually updated as changes are made to a worksheet, and includes any cell that has ever been used. For example, if A1 contains a value, and that value is deleted, cell A1 is still considered used. Sometimes, a worksheet will have a used range that is much larger than expected. This can cause performance problems and other unexpected behavior. One way to "reset" a used range is to delete all unused columns and rows.