The type area is the result of width and height of the typesetting. It must be set so that the front (recto) and side (verso) of a page are congruent.

The page number, also called pagination, is not part of the type area!

The type area determines the extent and appearance of a print work.

 

How to accurately lay down the type area:

The type setter defines the width of the typeset, which in turn determines its height. The following ways are available to do that:

  • type width : paper width = 3 : 4

    Resulting page margins:

    Inner margin: 2 parts
    Head margin: 2 1/2 parts
    Outer margin: 3 parts
    Foot margin: 4-5 parts

    type width : paper width = 2 : 3

    Resulting page margins:

    Inner margin: 2 parts
    Head margin: 3 parts
    Outer margin: 4 parts
    Foot margin: 5-6 parts

    type width : paper width = 5 : 8 (Golden section)

    Resulting page margins:

    Inner margin: 2 parts
    Head margin: 3 parts
    Outer margin: 5 parts
    Foot margin: 8 parts

When you define defining a type face, keep in mind that you shouldn't just do the mathematics, but you may also need to make visual corrections.