Paper Sizes: DIN C Series (ISO 269:1985)

The DIN C series (ISO 269:1985) includes the following formats:

[Translate to English:] DIN C0 917 x 1297 mm Quadruple sheet
DIN C1 648 x 917 mm Double sheet
DIN C2 458 x 648 mm Sheet
DIN C3 324 x 458 mm Half sheet
DIN C4 229 x 324 mm Quarter sheet (note paper)
DIN C5 162 x 324 mm Eighth sheet (page)
DIN C6 114 x 162 mm Half page
DIN C7 81 x 114 mm Quarter page (postcard)
DIN C8 57 x 81 mm Eighth page
DIN C9 40 x 57 mm

The aspect ratio is √2 : 1. It starts with the DIN C0 paper size, which measures 917 x 1297 mm.

From the base format of this DIN standard, the next smaller sizes are calculated with the formula width : height = √2 : 1.