Chinese Paper Sizes

The Chinese national standard GB/T 148-1997 defines a series of standard paper sizes for use in China. This standard establishes two main series of sizes - the A series and B series.

The A series follows the basic A0 to A10 sizes defined in the widely used ISO 216 standard, though with dimensions adjusted to the Chinese standard's precision guidelines. This includes standard office sizes like A4 and letter-sized papers. The B series defines larger sizes ranging from B0 to B10 for needs such as posters, documents, technical drawings, etc. These have dimensions following the same principles as the A series but starting from a larger base size.

Uniquely to China's national standard, a supplemental D series has also been established defining D0 to D6 sizes. This originated in the Republic of China era prior to 1949. The D sizes are tailored to Chinese needs and do not strictly follow ISO principles of aspect ratios or relative dimensions between sizes. Their distinguishing rule is that each size's short side is always 4mm longer than the next smaller size's long side. Together, the A, B and D series provide a comprehensive range of paper sizes standardized for use specifically in China.