A6 is a paper size that is often used for postcards. More exotic uses are small pocketbooks, library microfiche, and toilet paper.
A6 measures 105 × 148 millimeters or 4.13 × 5.83 inches. In PostScript, its dimensions are rounded off to 298 × 420 points. The matching envelope format is C6 (114 × 162 mm).
Part of the ISO 216 standard
A6 is part of a set or range of page sizes, called the ISO A or ISO 216 standard. This international standard is based on the German DIN 476 standard from 1922. A6 is actually often referred to as DIN A6. The Japanese have adopted the same set of sizes in their JIS P 0138-61 standard.
By folding an A6 in two along its shortest side, you create an A7 document. Two A6 pages next to each other in a spread equals the A5 paper size. This way a range of paper sizes are created from A0 (which has a surface of one square meter) to A10. The height/width ratio remains constant (1:1.41 or the square root of 2) for all sizes. The dimensions always get rounded to the nearest millimeter.
Resolution needed to print an A6 size picture
To output an image properly it needs to have a certain minimum resolution. The number of pixels depends on the required output quality.
- At 300 ppi (pixels per inch) the image needs to be 1240 x 1748 pixels. This is the required resolution for quality offset printing that will be viewed from a short distance (such as books, brochures, magazines, calendars,…). For photo books, it is also the optimum resolution but lower pixel count (down to 250 dpi) still gives great-looking photographs.
- At 150 ppi the image needs to be 620 x 874 pixels. This is the minimum resolution for newspapers or posters viewed from a fairly short distance.
A digital camera with decent image quality and a resolution of 2 megapixel or more can be used to print high-quality A6 size pictures.
None added yet.
Other sources of information
An elaborate yet easy to read page on the ISO 216 standard can be found here.