Crop marks are small lines printed beyond the edges of a page design to indicate the final trimming boundaries. They guide binders and printers when cutting large sheets into finished pages, cards, or broadsides. For poetry publications, crop marks ensure that a centered poem, border, illustration, or generous field of white space remains properly positioned after trimming. They are usually removed with the excess paper and do not appear on the finished book or broadside.

Crop marks (also called cut marks or trim marks) are subtle offset lines printed at the corners of a press sheet to indicate where the paper should be trimmed after printing. In textual bibliography and book design history, studying crop marks—and the bleed areas beyond them—helps researchers understand bookbinding formats, press imposition, and original sheet sizes. For poetry collectors and scholars examining rare broadsides or limited-edition chapbooks, the presence of un-trimmed crop marks often indicates proof copies or artisanal printing styles intended to preserve untrimmed deckle edges. Related terms include trim line, bleed, registration marks, and deckle edge.