The sen is the Japanese monetary unit equal to one hundredth of a yen.
Japan’s New Currency Act of 1871 established the yen as the main unit and divided it into 100 sen. The sen was further divided into 10 rin, creating a decimal structure that supported the country’s rapid modernization of its monetary system.
Sen coins were issued in denominations including one, two, five, ten, twenty, and fifty sen. Inflation made these small units increasingly impractical, and Japan stopped issuing sen coins for circulation after the Second World War.
The sen remains useful in historical descriptions and financial quotations, but it is not a circulating unit in modern Japan. The word should not be confused with “sen” in some other Asian languages, where it can have different monetary meanings.