Japan’s national flag has an official height-to-length ratio of 2:3.
Known as the Nisshōki in law and commonly as the Hinomaru, the flag is white with a red disk representing the sun. The disk is positioned at the center of the rectangular field, and its diameter is defined as three-fifths of the flag’s height under Japan’s official specifications.
Japan’s current legal flag specifications were established in 1999 by the Act on National Flag and Anthem. The red sun motif has deep cultural associations with Japan’s traditional description as a land where the sun originates. A common mistake is to confuse the flag’s 2:3 overall ratio with the separate measurement governing the sun disk.