Nations with Nuclear Weapons

There are eight sovereign states that have successfully detonated 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 Russian Federation (the successor state to the Soviet Union), 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 nuclear tests, namely India, Pakistan, and North Korea. North Korea had been a party to the NPT but withdrew in 2003. Israel is also widely known to have nuclear weapons, though it maintains a policy of deliberate ambiguity regarding this (has not acknowledged it), and is not known definitively to have conducted a nuclear test. According to the Stockholm International Peace Research Institute's SIPRI Yearbook of 2014, Israel has approximately 80 nuclear warheads.

According to Bulletin of the Atomic Scientists Nuclear Notebook 2014, the total number of nuclear weapons worldwide is estimated at 10,144.

South Africa developed nuclear weapons but then disassembled its arsenal before joining the NPT.  Nations that are known or thought to have nuclear weapons are sometimes referred to informally as the nuclear club.

Five states are known to have detonated a nuclear explosive before 1 January 1967 and are thus nuclear weapons states under the Treaty on the Non-Proliferation of Nuclear Weapons, they also happen to be the UN Security Council's permanent members with veto power on UNSC resolutions.  These nations are the United States, the United Kingdom, France, Russia and China.

From a high of 68,000 active weapons in 1985, as of 2016 there are some 4,000 active nuclear warheads and 10,100 total nuclear warheads in the world. Many of the decommissioned weapons were simply stored or partially dismantled, not destroyed.

It is also noteworthy that since the dawn of the Atomic Age, the delivery methods of most states with nuclear weapons has evolved with some achieving a nuclear triad, while others have consolidated away from land and air deterrents to submarine-based forces.

States with “Weapons of Mass Destruction”

Such weapons include nuclear or chemical or biological agents:

Albania, Algeria, Argentina, Australia, Brazil, Bulgaria, Canada, China, Egypt, France, Germany, India, Iran, Iraq, Israel, Japan, Libya, Mexico, Myanmar, Netherlands, North Korea, Pakistan, Philippines, Poland, Romania, Russia, Saudi Arabia, South Africa, South Korea, Sweden, Switzerland, Syria, Taiwan, Ukraine, United Kingdom, and the United States.

                                https://en.wikipedia.org/wiki/List_of_states_with_nuclear_weapons