JB1

The JB1 paper size has dimensions of 728mm x 1030mm (28.7 inches x 40.6 inches). With an area of approximately 0.75 square meters, JB1 is the second largest size in the Japanese JIS B paper size series after JB0. JB1 does not have any widely used alternative names. Its large size makes JB1 suitable for graphic design work, commercial printing projects, informational posters, and other applications requiring substantial printable space. As part of the standardized JIS B series, JB1 mirrors the dimensions of JIS A1 (half the area of JB0) and maintains the traditional Japanese "Kiku" aspect ratio of 1:√2. The origins of JB1 hearken back to Japan's adoption of the German DIN paper size standard in 1951 and subsequent local tweaks, resulting in the JIS Japanese Industrial Standards by the 1970s. While not as popular globally as the ISO sizes, JB1 fills an important role for industry printing applications in Japan and the East Asian market.