Currently we could change the page size of the PDF document by printing to Foxit Reader PDF Printer/Foxit PhantomPDF Printer with a designated Layout. Here are the procedures:
Open the PDF file that you want to change the page size.
Go to File > Print to bring up the Print window.
Choose Foxit PhantomPDF Printer/Foxit Reader PDF Printer, click on Properties, go to Layout tab, and choose a suitable page size, click on Ok to apply the change.
Click on Ok to print. Then you'll get the same PDF document with a different page size.
If you're using Foxit PhantomPDF, you could also enlarge the page size by following the following:
Go to Organize > Crop Pages > double-click on the page to bring up the Set Page Dimensions window. In Change Page Size section, please choose fix size or custom per your request.
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