What was the formal agreement ending Japan’s participation in World War II called?

The formal agreement ending Japan’s participation in World War II was called the Japanese Instrument of Surrender. It was the printed document through which Japan capitulated to the Allied powers on September 2, 1945.

The instrument recorded Japan’s acceptance of the Potsdam Declaration and required Japanese forces to cease hostilities and surrender. It was signed aboard USS Missouri in Tokyo Bay by Japanese representatives and delegates from nine Allied governments. The document took effect at 9:25 a.m. Japan Standard Time.

The instrument should not be confused with the Potsdam Declaration. The declaration was an Allied demand issued in July, while the instrument was the later document that formalized Japan’s surrender. It is also different from the Treaty of San Francisco, signed in 1951, which formally ended the state of war between Japan and many Allied countries and restored Japan’s sovereignty in 1952.