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I'm printing a booklet double-sided; how do I keep page numbers on the outer edge of every page?

Choose Right as the horizontal position and turn on Mirror the side on even pages: odd pages in the file carry the number on the right, even pages on the left, so it always lands on the edge away from the spine once printed on both sides. For an Arabic booklet that opens from the right, choose Left instead of Right.

Published · 3 min read

Why one corner for every page is not enough

Printed on one side only, a number on the right of every page is fine. Printed double-sided, each sheet holds two pages, and the two pages facing each other in an open booklet have opposite outer edges. If the number stayed on the right throughout, half the numbers would sit by the spine, hard to see and sometimes lost in the binding or under a staple.

The settings in the tool

  1. Get the page order final first. If a page needs moving, use Reorder PDF pages before numbering.
  2. Open PDF page numbering and choose the file.
  3. Set the vertical position to Bottom or Top, whichever suits your design.
  4. Set the horizontal position: Right for a booklet that opens from the left like an English book, or Left for an Arabic booklet that opens from the right.
  5. Tick Mirror the side on even pages, press Add numbers, and check the preview on one odd and one even page.

What happens in numbers

On an A4 page 595.28 points wide, with the default 10 mm margin (about 28.35 points), the number on odd pages is anchored 28.35 points in from the right edge, at 566.93 points from the left, and right-aligned. On even pages it moves to 28.35 points from the left edge and is left-aligned. The text always grows towards the inside of the page, so a longer label never runs off the paper.

If you pick Center, mirroring has no effect, because the centre is the centre on both sides.

The trap worth knowing

Mirroring follows the page's position in the file, not the number printed on it. That is deliberate, because the printer works from file order. Example: if you tick Skip the first page so counting starts after the cover, file page 2 carries the number 1, and since it is an even page in the file its number appears on the mirrored side. It can look odd on screen, but it is right on paper, because page 2 prints on the back of the cover.

  • Add a blank page or delete one after numbering and every side after it flips. That is why numbering is always the last step.
  • The tool does not rearrange pages into folded booklet order; that happens in your printer settings or at the print shop. It only puts the number in the right place.
  • Print one test sheet double-sided before the full run. It is the fastest way to confirm you picked the right side.

Common questions

Does mirroring work with numbers at the top too?

Yes. Mirroring only changes the horizontal side, whether the number sits at the top or the bottom of the page.

Do I need a bigger margin for stapled booklets?

A number on the outer edge is far from the staples, so the default margin is usually enough. Increase it if the print shop will trim the edges.