Creep

In multi-page booklet production, creep refers to the horizontal displacement of inner pages relative to the outer cover. As a signature is folded and stacked, the cumulative thickness of the block causes the central fold to shift outward. This mechanical shift means that content near the gutter does not align perfectly across all pages if laid out on a flat, uncorrected grid.

While negligible for thin brochures, creep becomes significant in thicker publications. Printers account for this by applying a correction factor during the imposition process, effectively shifting the inner page content slightly to ensure visual alignment once the book is bound. This adjustment is standard practice for perfect-bound or sewn booklets exceeding a certain page count, ensuring that text and images remain centered on the visible page area rather than being pushed toward the binding.