What is a3 a4?

A3 and A4 are paper sizes that are commonly used in printing, photocopying, and other office applications. A3 paper measures 297mm x 420mm (11.69 x 16.54 inches) while A4 paper measures 210mm x 297mm (8.27 x 11.69 inches). A3 paper is twice the size of A4 paper in both width and height.

A3 paper is often used for printing diagrams, posters, and other large documents, while A4 paper is more commonly used for printing standard documents such as letters, invoices, and proposals. Both A3 and A4 paper sizes are part of the ISO 216 standard, which sets out international standards for paper sizes.

In summary, A3 and A4 are two different paper sizes that are commonly used in offices and printing facilities. The difference between them is in their size, with A3 paper being twice as large as A4 paper.