If you're planning a booklet-type printed product – for example a program booklet, catalog, brochure or any saddle-stitched publication – then the final page count must always be divisible by 4. But why?
How is a booklet built up?
Booklet-type products consist of sheets of paper folded in half and stitched together.
Each sheet of paper:
- is printed on both sides,
- then we fold it in half,
- so one sheet of paper produces four pages: front – inside left – inside right – back.
That's why the page count has to be divisible by 4
For example, if you want a 16-page booklet, it consists of exactly 4 folded sheets (4×4 pages).
But if you're planning 18 pages, the nearest feasible page count is 20 – that is, 2 blank pages are automatically added at the end, unless you fill them.
What should you do if it doesn't come out to 4?
If your planned content doesn't add up to a page count divisible by 4, you have a few options:
- Top up the page count with useful content – for example acknowledgments, a notes page, a message or a picture.
- Deliberately leave a blank page at the end of the booklet, perhaps for note-taking.
- Switch to a different type of binding, if the format requirements allow it (e.g. with perfect binding or spiral binding, a page count in multiples of 4 is not mandatory).
