Koban

Koban is the smallest of the standard rectangular print formats, measuring approximately 22 x 16 centimeters. Its compact size made it economical for mass production and popular for categories like greeting cards, small souvenirs, and affordable prints for everyday decoration.

During the Edo period, koban prints served a different market segment from the larger oban format — they were accessible to buyers who could not afford larger, more elaborate prints. The format was also common for book illustrations and small-format series. Despite the modest dimensions, skilled artists and printers could produce remarkably detailed and beautiful works in koban format.

In the shin-hanga and sosaku-hanga eras, koban-format prints were sometimes produced for special editions, greeting cards (particularly New Year's cards, or nengajo), and portfolio collections. Their small size makes them popular with collectors who have limited display space, and they often represent a more affordable entry point for beginning collectors of Japanese woodblock prints.