The most widely used for general printing and letterhead stationery is the A series. The most common of these sheet sizes is the international letterhead size A4 , which measures 8-1/4 x 11-3/4 in, or 210 x 297 mm. These paper measurements are defined by the ISO 216 standard. The dimensions of the A series paper sizes , as defined by the ISO 216 standard, are given in the table below the diagram in both millimetres and inches ( cm measurements can be obtained by dividing mm value by 10). The A Series paper size chart, below left, gives a visual representation of how the sizes relate to each other - for example A5 is half of A4 size paper and A2 is half of A1 size paper. The dimensions of A4 size is 21 x 29.7 cm or 210 x 297 mm or 8.3 x 11.7 inches. A4 Size Dimensions in cm = An A4 sheet measures 21 cm in width and 29.7 cm in length. These user-friendly dimensions make A4 paper incredibly versatile. It’s the standard for printing, letters, brochures, posters, menus, magazines, and calendars – just to name a few applications. Use our calculator to perform the calculation effortlessly ...