On what date did Emperor Hirohito announce Japan’s acceptance of the Potsdam Declaration?

Emperor Hirohito announced Japan’s acceptance of the Potsdam Declaration on August 15, 1945. His recorded radio address, known as the Gyokuon-hōsō, was broadcast at noon Japan Standard Time.

It was the first time most Japanese civilians had heard the emperor’s voice. Hirohito used formal court language, so many listeners did not immediately understand that Japan had surrendered. The broadcast followed intense debate within Japan’s wartime leadership and the emperor’s intervention in favor of accepting the Allied terms.

August 15 is often called V-J Day in countries that received the news on that date. It should not be confused with September 2, when Japanese representatives formally signed the Instrument of Surrender aboard USS Missouri. The two dates mark related but distinct stages: public announcement first, legal ceremony later.