PDF Reverse Pages

The problem this solves

A stack of paper fed into a document feeder face-up when the scanner expects face-down produces a PDF in exact reverse order. So does scanning a stack that was sitting in an output tray, where the last page printed ends up on top. Both are mechanical, both affect the entire document uniformly, and both are fixed by a single reversal rather than by dragging pages around.

Check it is a clean reversal first

Reversal is the right fix only when the whole document is backwards. If the pages are interleaved, which happens when a duplex scan is done as two separate passes, reversing makes it worse. The quick test is to look at the first and last pages: if the last page of the file is the document's cover and the first is its final page, it is a clean reversal. If the order alternates between unrelated pages, you need an interleave instead.

Reversal is its own inverse

Applying it twice returns the original order exactly, so there is no risk in trying it. Nothing is re-encoded and no content changes; only the page sequence in the document's page tree is rewritten, which means the operation is lossless and instant even on a large scan.

What follows the pages

Annotations, form fields and anything anchored to a page move with it. Bookmarks may not: an outline that references absolute page positions will point at the wrong content afterwards, so check the panel if the document has one. Page numbers already printed on the pages obviously do not renumber, so a reversed document reads 10, 9, 8 in its printed footers. Renumber after reversing if that matters.

Local processing

The page tree is rewritten in your browser and the file is never uploaded.