List of states with nuclear weapons
Eight sovereign states have publicly announced successful detonation of nuclear weapons. Five are considered to be nuclear-weapon states (NWS) under the terms of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). In order of acquisition of nuclear weapons these are the United States, the Soviet Union (now Russia), the United Kingdom, France, and China.
Since the NPT entered into force in 1970, three states that were not parties to the Treaty have conducted overt nuclear tests, namely India, Pakistan, and North Korea. North Korea had been a party to the NPT but withdrew in 2003.
Israel is also generally understood to have nuclear weapons, but does not acknowledge it, maintaining a policy of deliberate ambiguity, and is not known definitively to have conducted a nuclear test. Israel is estimated to possess somewhere between 75 and 400 nuclear warheads. One possible motivation for nuclear ambiguity is deterrence with minimum political cost.
States that formerly possessed nuclear weapons are South Africa (developed nuclear weapons but then disassembled its arsenal before joining the NPT) and the former Soviet republics of Belarus, Kazakhstan, and Ukraine, whose weapons were repatriated to Russia.
According to Stockholm International Peace Research Institute (SIPRI), the worldwide total inventory of nuclear weapons as of 2021 stood at 13,080. Around 30% of these are deployed with operational forces, whilst more than 90% are owned by either Russia or the United States.