The day Japan announced its surrender in 1945 is commonly called V-J Day in the United States.
“V-J” means “Victory over Japan.” President Harry S. Truman announced Japan’s surrender on August 14, 1945, in Washington, while the news arrived in different time zones. In Japan, the emperor’s public broadcast was heard on August 15.
The celebrations marked the end of the Pacific War and, in practical terms, the end of World War II. Crowds gathered in cities across the Allied world, with especially famous celebrations in New York’s Times Square.
V-J Day can refer either to the August announcement or, in some countries and historical contexts, to the later formal surrender on September 2. V-E Day, by contrast, marked Germany’s surrender in Europe earlier in 1945.