B6

The B6 envelope has compact dimensions of 176mm x 125mm, giving it a surface area of 22,000 mm2. The maximum enclosure size is typically around 120mm x 170mm. As part of the ISO 269 "B" series, the B6 sits between the larger B5 and smaller B7 sizes. It shares the same 1.414:1 width-to-height ratio as other ISO sizes. The B6 is uniquely suited to hold an A4 sheet of paper folded twice to become an A6 sheet at 105mm x 148mm. This allows it to accommodate small brochures, flyers, invitations or other documents originating from A4 paper. While not as widely used as C6 envelopes, the squarish B6 provides a bit more space and serves as a versatile option between postcards and larger envelopes. It sees primary use in Europe and Asia, originating from the German DIN 476 standard that influenced ISO paper formats.