Written By: Paula Fargo

paula fargo

Why is 4 a Magic Number in Printing?

A Mr. E. Buzz Miller from Baltimore, Maryland asks:

Q: I want you to print one of those booklet-thingies for me, you know, the kind of thing where the pages are folded and there are 2 staples in the middle? How can I do that?

A: Thanks for contacting us about your booklet job, Mr. Miller, we are happy to explain how this process works. In the world of high quality printing here in Baltimore, there are very few topics that cause more consternation than creating booklets for printing. Self-cover vs hard cover? Mechanical binding vs perfect binding vs saddle stitching? Flat size vs finished size? And then there is the deep, dark “MYSTERY OF FOUR.”

When producing a saddle stitched book (the kind where the staples are on the folded spine of the booklet), the number of “pages” needs to be divisible by 4! And you thought your trusted Baltimore Printer didn’t need to be good at math!

If you’re wondering why for goodness sake your page numbers have to be divisible by 4, I’m here to enlighten you. If you take a sheet of paper and fold it in half, and write a number on the lower right hand corner of each rectangle, you will get 4, because each sheet of paper has a front and a back (2) and each sheet of folded paper has a left and a right (2), making 4 “sides.” You can see that putting together a bunch of these folded sheets, you will have a total number of sides that are divisible by 4. That does not necessarily mean you need to have printing on all of the sides, just that you will have those number of pages to deal with.

As an example, if you give me a pdf that has 6 pages and want a folded booklet, I will tell you that 2 of the pages will have to be blank (6+2=8 which is divisible by 4). This can be confusing and complicated, so it is best to rely upon your full service printing vendor to guide you with this print project.

There are all sorts of fun ways to put books together, and we are happy to show you some if you’d like to pop into our store, we’ve got lots of samples to show you.