Lineweight

Lineweight is the visual thickness of a line in a drawing or graphic. It influences legibility, emphasis, and perceived hierarchy, and is a fundamental consideration in technical illustration, cartography, and vector artwork. The term is also used when describing stroke thickness in typography and digital graphics.

In technical drawing, lineweight is usually defined by a hierarchy of weights or pen widths. Thicker lines convey visible outlines or important features, while thinner lines represent secondary details such as hidden features or dimension lines. Standards in different regions, such as ISO and ANSI, provide guidelines, but exact values vary by discipline and scale.

In digital tools, lineweight translates to a stroke width or pen width for vector paths. It is commonly measured in points, millimeters, or pixels, depending on the medium. On screen, anti-aliasing can affect perceived weight, and on print, the chosen DPI and ink or toner influence final thickness.

Practical use involves establishing a clear visual hierarchy: assign consistent weights across a drawing set, test legibility at the intended scale, and avoid excessive variation that can clutter the image. When communicating with others, well-chosen lineweights help readers distinguish geometry, annotations, and construction details.