JB4

The JB4 paper size has dimensions of 257mm x 364mm (10.1 inches x 14.3 inches). With an area of approximately 0.0935 square meters, JB4 is a smaller format in the JIS B series. JB4 does not have any common alternate names. Its compact size makes JB4 suitable for needs like business documents, letter writing, catalogs and magazines, brochures, greeting cards, and various commercial printing uses where limited space is available. As part of the standardized Japanese B range, JB4 upholds the traditional “Kiku” aspect ratio of 1:√2. The origins of JB4 date back to Japan’s postwar embrace of the German DIN standard in 1951 and subsequent local fine-tuning into Japanese Industrial Standards including the JIS B sizes by the 1970s. While not globally used compared to ISO sizes, JB4 fills a practical small-format printing role across Japan and the East Asian region.