Page Rotation is a metadata value that is exclusive to PDF documents. There, it’s often expressed abbreviated as “page rot”.
This meta information is rather self-explanatory. It gives an indication of how and in which direction a page inside a PDF document was rotated. Especially in merged documents or when a PDF consists of both landscape and portrait format pages, this information can be quite valuable.
The value found for Page Rotation is typically one of three numbers:
These numbers specify the degree of rotation that was applied to the page. Usually, the degree is given for the clockwise rotation. This means the rotation starts from the top, moving to the right.
In special cases, counterclockwise rotation occurs as well. Then, it’s often expressed as -90° instead of the plain 90°.