Recently, I read a paper that opened by default in a two-page layout, like a book. I wondered how that setting was saved inside the PDF.
The setting is controlled by the PDF’s Initial View properties. In Adobe Acrobat, or another PDF editor that can modify document properties, you can set it like this:
- Open the PDF file.
- Choose File -> Properties.
- Open the Initial View tab.
- Under Page Layout, choose the default layout you want, such as Single Page, Two-Up, or Two-Up Continuous.
- Save the PDF.
After saving, the PDF should request that layout when it is opened. Different PDF readers may still apply their own preferences, so this is best understood as a document-level default rather than an absolute guarantee.