The United States announced Japan's surrender on August 14, 1945, marking the American V-J Day celebration.
President Harry S. Truman broadcast the news to the American public on the evening of August 14, Washington time. Because Japan was several time zones ahead, the announcement was heard there on August 15, when Emperor Hirohito's surrender message was also broadcast.
This creates a common date mix-up. August 14 is associated with the announcement in the United States and much of the Americas, while August 15 is the date commonly observed in Japan and the United Kingdom. The formal legal signing of Japan's surrender occurred later, on September 2, aboard USS Missouri in Tokyo Bay.
Truman specifically distinguished the announcement from the formal end of the war, saying that the official proclamation would wait for Japan to sign the surrender terms.