Cropping PDF pages in PDF file doesn’t reduce PDF pages’ size because information is merely hidden, not discarded. By resetting the page size, you can restore the PDF pages and their contents to their original conditions. Please do as follows to undo cropping on all cropped pages in a PDF file:
1: Open PDF file with Foxit PhantomPDF ,go to Organize tab>Crop Pages,double-click on the PDF page to bring up the Set Page Dimensions dialog box.
2: Type the page number range for all pages in the PDF file in the Page: blank field under Page Range part.
For example, the PDF file contains 19 pages in total, I have to input 1-19 in the Pages: blank field.
3:Check Remove White Margins option,click on Set To Zero button,hit ok to reset the margins to the original page dimensions for all PDF pages in the PDF file.