Japanese is the principal language of the Japonic language family spoken by the Japanese people. It has around 120 million speakers, primarily in Japan, the only country where it is the national language, and within the Japanese diaspora worldwide.

Altaic is a controversial proposed language family that would include the Turkic, Mongolic and Tungusic language families and possibly also the Japonic and Koreanic languages. The hypothetical language family has long been rejected by most comparative linguists, although it continues to be supported by a small but stable scholarly minority. Speakers of the constituent languages are currently scattered over most of Asia north of 35° N and in some eastern parts of Europe, extending in longitude from the Balkan Peninsula to Japan. The group is named after the Altai mountain range in the center of Asia.