On what date did Japan’s formal surrender document get signed in 1945?

Japan’s formal surrender document was signed on September 2, 1945.

The ceremony took place in Tokyo Bay aboard the American battleship USS Missouri. Japanese representatives signed the Japanese Instrument of Surrender, followed by representatives of the Allied powers. The ceremony formalized Japan’s capitulation and is generally treated as the official end of World War II.

Japan had announced its decision to surrender weeks earlier. Emperor Hirohito’s radio broadcast on August 15 told the Japanese public that the government had accepted the terms of the Potsdam Declaration. Fighting and military activity did not instantly disappear everywhere, so the later signing supplied a formal legal and ceremonial conclusion.

The date can cause confusion because “V-J Day” is also used for August 15 in Japan and August 14 in the United States, reflecting the surrender announcement and time-zone differences. September 2 is the date of the signed instrument and the formal ceremony.