In the United States, Japan’s initial World War II surrender announcement was made on August 14, 1945.
The date differed across regions because of time zones. Japan announced the surrender to its population on August 15, while the announcement reached the United States and much of the Americas on August 14. This is why historical references sometimes give two dates for V-J Day.
The announcement followed Japan’s acceptance of the Allied terms in the Potsdam Declaration. Emperor Hirohito recorded a radio address explaining that Japan would accept the declaration, and it was broadcast in Japan at noon on August 15 local time.
The formal legal surrender occurred later, on September 2, 1945, when Japanese representatives signed the Instrument of Surrender aboard USS Missouri in Tokyo Bay. Thus, August 14 refers to the American announcement date, while September 2 marks the signing ceremony and official end of the war.