What was the formal name of the document Japan signed on September 2, 1945, ending World War II hostilities?

The formal document Japan signed on September 2, 1945, was the Japanese Instrument of Surrender.

The instrument declared Japan’s unconditional surrender and required Japanese forces to cease hostilities, disarm, and comply with the orders of the Supreme Commander for the Allied Powers. It was signed aboard USS Missouri in Tokyo Bay.

Foreign Minister Mamoru Shigemitsu signed for the Japanese government, and General Yoshijirō Umezu signed for Imperial General Headquarters. Douglas MacArthur accepted the surrender for the Allied Powers, followed by representatives of nine Allied countries.

The instrument is often confused with the Potsdam Declaration, issued on July 26, 1945. The declaration stated the Allied terms and called on Japan to surrender; the later instrument recorded Japan’s formal acceptance. The Treaty of San Francisco was different again: it came into force in 1952 and formally ended the state of war between Japan and many Allied countries.