Why does my .doc mess up when converted to .pdf?

[farmerjohn1324]

I am using an online .doc to .pdf converter, but when it converts, the pages are out of line. It is a book and the pages are lined up neatly in the .doc, but when it's on the .pdf, what is supposed to be at the top of the page is not at the top of the page. There are extra spaces at the top so the headers are in the middle of the page.

I am using http://convertonlinefree.com/

 

[johnb35]

As far as I know when converting text documents, it always will. Even going from works to word everything was different and they are both microsoft products.