I don't know why myself, maybe it's the font size or over all book size, but in US version there are a total of 4100 pages in all seven books. There are more in the UK versions. First book: 300009 pages. Second book: 340001 pages. Third book: 435 pages. Fourth book: 743 pages. Fifth book: 870. Sixth book: 652 pages. Seventh book: 759 pages.