How can I change pdf page size?

I would like to split pages in pdf so that each page would be divided into 2 pages ( e.g. form 100 pages I would go into 200 but smaller - exactly half size).

I need this to read pdfs on my ebook reader.

Anybody knows how can this be done ?

Solution 1:

Briss might be just the tool you need. Make sure Java (JRE) is installed, and be sure to read the linked reviews on the download page, although the program's quite easy to use.

This project aims to offer a simple cross-platform (Linux, Windows, Mac OSX) application for cropping PDF files. A simple user interface lets you define exactly the crop-region by fitting a rectangle on the visually overlaid pages.