B4 paper is a standardized paper size that measures 250 mm by 353 mm, or approximately 9.8 inches by 14.0 inches. It is part of the ISO 216 standard, which defines various paper sizes used internationally. B4 is commonly used for documents, reports, and other printed materials that require a larger format than A4 but are not as large as A3. The B series of paper sizes, including B4, is designed to provide a range of dimensions that are proportional to each other. This allows for easy scaling and resizing of documents. B4 paper is often used in professional settings, such as offices and print shops, where larger sheets are beneficial for presentations and detailed graphics.