The page count (or total number of pages) of saddle stitched booklets includes all sides of the final book, including the front and back cover, and must always be a multiple of 4.
Saddle stitched booklets are produced by folding multiple sheets of paper in half, collating and then stapling in the centre. As an example, two 17" x 11" sheets that are bound to an 8.5" x 11" booklet would count as 8 pages. Using the same example, if three 17" x 11" sheets were saddle stitched, the result would be an 8.5" x 11" booklet with 12 pages.
Example 1:
Page 1 - Front cover
Page 2 - Inside front cover
Page 3 - First "internal" page (right-hand-side)
Page 4 to 6 - Other internal pages
Page 7 - Inside back cover
Page 8 - Back cover
Example 2:
Page 1 - Front cover
Page 2 - Inside front cover
Page 3 - First "internal" page (right-hand-side)
Page 4 to 10 - Other internal pages
Page 11 - Inside back cover
Page 12 - Back cover