PA5

The PA5 paper size has dimensions of 140mm x 210mm, giving it a total surface area of 0.0294 square meters. As part of the PA transitional paper size system proposed in 1975, PA5 directly bridges the gap between the PA sizes and ISO 216's A5 format. Notably, PA5 shares the same height as A5 but gains additional horizontal space with its wider width. This makes PA5, alongside its vertical cousin PA4, one of the more popular entries in the PA series. PA5 is sometimes known by the alternative name Extra A5, befitting its nature as an extended version of A5. Typical use cases include magazines, books, and catalogs where the extra width facilitates content presentation in a familiar A5-like form factor. Despite being rejected for standardization along with the rest of the PA series, PA5 persists as an important transitional size right between PA4 and A5 for horizontal applications demanding just slightly more space than A5 alone accommodates. Though it lacks a rich history of its own, PA5’s sustained use demonstrates the utility of this horizontal A5 variant for publications and binding needing a little extra width.