C10 size

28 × 40 mm · 1.1 × 1.57 in · 79.4 × 113.4 pt

Where it comes from

Half of C9: the C9 sheet's long side (57 mm) halves and rounds down to 28 mm — ISO 216's halve-and-floor rule.

Source: Markus Kuhn — International standard paper sizes (CC BY 4.0)

Pixels at print resolutions

DPIPixels (portrait)Typical use
7279 × 113legacy screens
96106 × 151CSS reference
150165 × 236everyday print
300331 × 472quality print
600661 × 945fine art / line work

The family

  • Fold C9 in half and you're holding C10.
  • Area: 0.0011.