18column

18column is a grid-based layout concept used in typography and interface design. It consists of eighteen vertical columns of equal width, with consistent gutters and margins to organize content.

Content blocks can span any number of columns, from one to many, allowing flexible compositions while preserving alignment with the grid. The system supports nesting and modular reuse across pages, helping maintain visual consistency across a publication or interface.

In terms of structure, gutters define whitespace between columns and outer margins establish the usable canvas width. At smaller viewports, the grid can reduce the number of active columns to maintain balance and legibility. In print contexts, the 18column grid guides magazine and report layouts; in digital design, it translates to a grid system implemented with CSS grid or similar frameworks.

The 18column grid is one option among other modular grids, such as 12-column or 24-column systems. A higher-column count offers finer granularity for mid-size layouts, while still supporting responsive adjustments for wide screens and mobile devices.

Implementation in web design typically uses CSS grid: define 18 equal tracks with grid-template-columns: repeat(18, 1fr); then place content by assigning column spans, for example grid-column: span 4;, to achieve the desired alignment within the overall grid.

See also: grid system, CSS Grid, editorial grid, modular grid, responsive design.