Manual duplex printing helper
Does your printer lack automatic double-sided printing? This tool splits your PDF into two files — odd pages, then even pages — in the right order so the second pass lines up correctly once the stack of sheets is flipped back into the tray.
How it works
On a printer without automatic duplex, you have to print one side of each sheet, put the stack back in the tray, then print the other side. The tool splits your PDF into two files: one for all the odd pages (1, 3, 5…) and one for all the even pages (2, 4, 6…). For the second file, the page order is reversed so that, once the stack of sheets printed on the "front" is flipped back into the tray, the even page printed on each sheet matches its odd page.
Why two stack-flipping settings ("long edge" / "short edge")?
Not every printer or user flips the stack the same way to put it back in the tray: some flip it by rotating it around its long edge (the most common), others around its short edge. These two motions call for a different page order for the back side to line up correctly — if your first attempt comes out misaligned or upside down, try again with the other setting.
How many sheets of paper will I use?
One sheet for every 2 pages of the document (rounded up if the page count is odd, in which case the back of the last sheet stays blank). A 10-page PDF therefore needs 5 sheets printed double-sided.
100% local processing in your browser (WebAssembly) — your PDF is never sent to a server.