Justification settings consist of minimum, desired, and maximum values for: spacing between letters; spacing between words; and in some cases, how much the glyphs themselves can be stretched or squeezed. (Note that most type and design professionals consider glyph scaling to be a type crime.) Justification parameters can also include other more specific settings, such as how to treat a partial line or single word appearing at the end of a paragraph – fully justified, flush left, flush right, or centered.

Page-layout software uses a combination of both hyphenation and justification to achieve the best results. While preset H&J settings are intended to work well for general use, they are not one-size-fits-all. These settings can be customized to minimize stretching or squeezing and to maximize readability – as well as to take into account a client’s needs and preferences.

Several factors can affect H&J settings. These include the typeface(s) being used, line length and/or column width, as well as the overall design objective. For instance, in the case of newspapers and other publications where there is no time to hand-edit the type or copy, H&J settings might be very liberal, to fit in as much copy as possible, with less attention to readability and aesthetics. On the other hand, a higher-end, less ephemeral publication, brochure, or annual report might follow more rigorous type and design standards, including more conservative H&J settings, to keep the typography as natural, undistorted, and enticing to read as possible.