Because test results are occasionally disputed, the best estimate is that more than 2,000 nuclear weapons have been tested.

The totals that follow are official counts, by nation:

1,054: The United States conducted 904 tests at the Nevada National Security Site (NNSS; previously called the Nevada Test Site and the Nevada Proving Grounds), near Las Vegas. Another 106 US tests were in the Pacific Ocean, most at the Pacific Proving Grounds in the Marshall Islands. Others were in the South Atlantic Ocean, Alaska, Colorado, Mississippi, and New Mexico.

715: The Union of Soviet Socialist Republics detonated 969 nuclear weapons during 715 tests, according to the nation’s official count. The Soviet Union primarily used test sites at Semipalatinsk and Novaya Zemlya. Other tests were in Kazakhstan, Russia, Turkmenistan, Ukraine, and Uzbekistan.

210: France performed 210 tests, most underground, In the Algerian Sahara Desert and at or near the Fangataufa and Moruroa Atolls in French Polynesia.

45: The United Kingdom conducted 45 tests, nearly half of them (21) in Australia, its Montebello Islands, Maralinga, and Christmas Island. The UK tested 24 times at the NNSS, in joint testing with the United States.

45: China‘s 45 tests were at Lop Nur Nuclear Weapons Test Base in Xinjiang.

6: India, at Pokhram.

6: Pakistan, at Ras Koh Hills and Chagai.

6: North Korea. This is the only nuclear nation that still tests weapons, the last on September 3, 2017.

More Info: en.wikipedia.org