The Nuclear Testing Tally

Last Reviewed
January 2024

Contacts: Daryl Kimball, Executive Director, (202) 463-8270 x107

Since the first nuclear test explosion on July 16, 1945, at least eight nations have detonated over 2,000 nuclear tests at dozens of test sites, including Lop Nor in China, the atolls of the Pacific, Nevada, and Algeria where France conducted its first nuclear device, Western Australia where the U.K. exploded nuclear weapons, the South Atlantic, Semipalatinsk in Kazakhstan, across Russia, and elsewhere.



Most of the test sites are in the lands of indigenous peoples and far from the capitals of the testing governments. A large number of the early tests—528—were detonated in the atmosphere, which spread radioactive materials through the atmosphere. The 1963 Limited Test Ban Treaty brought about the end of most, but not all, nuclear test explosions in the atmosphere. However, many underground nuclear blasts have also vented radioactive material into the atmosphere and left radioactive contamination in the soil.

Type of TestUnited StatesUSSR/ RussiaUnited KingdomFranceChinaIndiaPakistanNorth KoreaTotal
Atmospheric215219215023000528
Underground81549624160223261,528
Total1,0301 (Note: total does not include the atomic bombings of Hiroshima and Nagasaki.)71545210453262,0562


Through nuclear test explosions, the nuclear testing nations have been able to proof-test new warhead designs and create increasingly sophisticated nuclear weapons. The overwhelming majority of the nuclear weapon test detonations were for "weapons development" and "weapons effects" purposes.

Following Russian and U.S. nuclear testing moratoria, multilateral negotiations on a global Comprehensive Test Ban Treaty (CTBT) began in 1994 and were concluded in 1996. The treaty was opened for signature on September 24, 1996. The CTBT, which prohibits "any nuclear weapon test explosion or any other nuclear explosion" and established an international test monitoring and verification system, has not yet entered into force.

United States
(1,030)
First test:
July 16, 1945.
Last test:
Sept. 23, 1992.
Signed CTBT:
Sept. 24, 1996.

USSR/Russia
(715 tests)
First test:
Aug. 29, 1949.
Last test:
Oct. 24, 1990.
Deposited CTBT Ratification:
June 30, 2000.

United Kingdom
(45 tests)
First test:
Oct. 3, 1952.
Last test:
Nov. 26, 1991.
Signed CTBT:
Sept. 24, 1996.
Deposited CTBT Ratification:
Apr. 6, 1998.

France
(210 tests)
First test:
Feb. 13, 1960.
Last test:
Jan. 27, 1996.
Signed CTBT:
Sept. 24, 1996.
Deposited CTBT Ratification:
Apr. 6, 1998.

China
(45 tests)
First test:
Oct. 16, 1964.
Last test:
July 29, 1996.
Signed CTBT:
Sept. 24, 1996.

India
(3 tests2)
First test:
May 18, 1974.
Last test:
May 13, 1998.
Not a CTBT signatory.

Pakistan
(2 tests3)
First test:
May 28, 1998.
Last test:
May 30, 1998.
Not a CTBT signatory.

North Korea
(6 tests)
First test:
Oct. 9, 2006.
Last test:
Sept. 3, 2017.
Not a CTBT signatory.

YearUnited StatesUSSR/ RussiaUnited KingdomFranceChinaIndiaPakistanNorth KoreaTotal
19451       1
19462       2
19470       0
19483       3
194901      1
195000      0
1951162      18
19521001     11
19531152     18
19546100     16
19551860     24
19561896     33
195732167     55
195877345     116
1959000     0
19600003    3
1961105902    71
1962967921    178
196347003    50
1964459231   60
19653814141   58
19664818073   76
19674217032   64
19685617051   79
19694619002   67
19703916081   64
19712423051   53
19722724042   57
19732417061   48
197422211911  55
197522190210  44
197620211540  51
197720240910  54
1978193121130  66
1979153111010  58
1980142431210  54
1981162111200  50
1982181911010  49
198318251920  55
198418272820  57
198517101800  36
19861401800  23
198714231810  47
198815160810  40
19891171900  28
1990811620  18
1991701600  14
1992600020  8
1993000010  1
1994000020  2
1995000520  7
1996000120  3
1997000000  0
19980000022 4
1999-20050000000 0
2006000000011
2007-2008000000000
2009000000011
20100000000030
2011000000000
2012000000000
2013000000011
2014000000000
2015000000000
2016000000022
2017000000011
2018-2019000000000
Total1,03071545210453262,056

NOTES

1. The total number and yearly listing of U.S. nuclear test explosions listed in this fact sheet are based on the figures published in United States Nuclear Tests: July 1945 through September 1992  DOE/NV-209 (Rev. 14), December 1994. The Department of Energy has since pubished two revisions of the pubication that slightly revise these numbers and reassign the purposes originally described for certain nuclear test explosions.

2. This "Nuclear Testing Tally" includes nuclear tests announced or reported by governments and/or intergovernmental organizations. As such, it does not take into account the "Vela Incident" of 1979 because it has not yet officially been determined by any government or intergovernmental organization to have been a nuclear test explosion. However, there is strong evidence and analysis by independent experts that suggests it was an atmospheric nuclear weapon test explosion.

3. In accordance with the definition of a nuclear test contained in the 1974 Threshold Test Ban Treaty and to allow accurate comparison with other countries' figures, India's three simultaneous nuclear explosions on May 11 are counted as only one nuclear test, as are the two explosions on May 13. Likewise, Pakistan's five simultaneous explosions on May 28 are counted as a single test.

4. In the article "Radionuclide Evidence for Low-Yield Nuclear Testing in North Korea in April/May 2010," Lars-Erik De Geer argued that the xexon and barium isotope concentrations in air currents from North Korea in April and May of 2010 were consistent with two low-yield nuclear tests. However, this theory was largely debunked when the Earth Institute at Columbia University measured seismology records and determined that no well-coupled explosion larger than one ton could have occurred during that timeframe. According to the report, such a low yield explosion would have been incapable of advancing the North Korean's technical understanding of a nuclear weapon explosion.