D6

With small dimensions of 96 mm x 136 mm, the D6 format represents one of the minor sizes in the German DIN 476 paper size standard published in 1922. Its 0.013 square meter area between ISO A7 and A6 allowed convenient archiving of technical specifications as engineering and manufacturing industries relied more on standardized sizes in the mid 20th century. The elongated width-to-height proportions of 1.25 match graphing needs for landscape orientations as well. Possible origins stem from prior German and Prussian book publishing formats that the DIN system aimed to consolidate.

While seeing some use for graphs, charts, notes, and ledger keeping, the diminutive D6 ultimately occupied a niche as office equipment favored ISO standards. Just as C series envelopes and B series intermediates failed to gain traction over ISO 216, D6 and other minor D sizes were likely obsolete by the late 1900s. However, the DIN 476 specification's inclusion of the meticulous D variants demonstrated intent to furnish documents at practically any dimensional scale alongside the common A, B, and C sizes. The D6 sheet in a way preserved hyper-specific sizing for posterity.