A2 size refers to a specific paper dimension that measures 420 millimeters by 594 millimeters, or approximately 16.5 inches by 23.4 inches. It is part of the A series of paper sizes defined by the ISO 216 standard, which is widely used in many countries around the world. A2 is commonly used for posters, drawings, and other large-format prints. In the A series, A2 is the second size in the sequence, following A1 and preceding A3. Each size in the series is half the area of the previous size when folded in half parallel to its shorter sides. This makes A2 a versatile choice for various creative and professional applications.