At what time did the 1945 Japanese surrender officially take effect?

The 1945 Japanese surrender officially took effect at 9:25 a.m. Japan Standard Time.

The surrender ceremony had begun shortly after 9 a.m. aboard USS Missouri in Tokyo Bay. The Japanese and Allied representatives signed the instrument in a prescribed sequence, and the formal proceedings ended at 9:25 a.m. Japan time.

This precise time is different from several other important times connected with Japan’s surrender. Emperor Hirohito’s recorded announcement was broadcast at noon on August 15. The atomic bomb over Hiroshima detonated at 8:15 a.m. local time on August 6, while the Nagasaki bombing occurred on August 9.

The 9:25 a.m. time marks the completion of the legal surrender ceremony, not the moment when Japanese civilians first learned of the decision. It also does not identify the date of V-J Day in every country, because some countries commemorated the announcement and others emphasized the formal signing.