Japan's signed surrender officially took effect at 9:25 a.m. Japan Standard Time on September 2, 1945.
The Japanese Instrument of Surrender was signed aboard the USS Missouri in Tokyo Bay. The first Japanese signature, by Foreign Minister Mamoru Shigemitsu, was placed at 9:04 a.m. General Yoshijirō Umezu signed for Imperial General Headquarters at 9:06, and General Douglas MacArthur accepted the surrender at 9:08.
Representatives of the United States, China, the United Kingdom, the Soviet Union, Australia, Canada, France, the Netherlands, and New Zealand then signed. MacArthur closed the proceedings at 9:25 a.m., the time recorded for the surrender to become effective.
This exact time differs from the noon broadcast on August 15, when Hirohito announced Japan's acceptance of the Allied terms. The two times mark separate stages: public announcement and formal legal capitulation.