How do I Change a PDF Form From a Full Page to Half Page?by Timothy Allen
PDF files are the most popular, and have become the default, method for creating easy-to-distribute documents and forms that cannot generally be edited by anyone but their creator. Adobe's Acrobat program is the primary method of creating PDF files, though there other programs are now capable of making files in the PDF format. Once you save a PDF file, it is generally unalterable unless you have Adobe Acrobat. With Acrobat, however, it is possible to make any edit or adjustment to a PDF that you want, including reducing the page size from a half page to a full page.
Open and Modify Your Document
Choose "File" > "Open" to open a saved PDF document in Acrobat.
On the menu, choose "Document" > "Crop Pages". A window will open up with a graphical representation of your document on the right and a series of smaller selectors on the left that are labeled: "Top", "Bottom", "Left", and "Right".
Click the up arrow on the spinner next to the "Bottom" selector a couple of times. A line will appear at the bottom of the graphical representation of your page on the right and advance up slightly every time you press the spinner.
Continue clicking the up arrow on the spinner until the line on the representation is where you would like the page to be cropped. Press "OK" when you are done. Acrobat will automatically trim off the bottom section of your document to the page size you selected.