Nine countries currently possess nuclear weapons. Five are officially recognized under international treaty, and four others have developed arsenals outside that framework. Together, these nations hold an estimated 12,000 or more nuclear warheads, though the vast majority belong to just two of them: the United States and Russia.
The Five Recognized Nuclear States
The Nuclear Nonproliferation Treaty (NPT), which now has 190 member states, formally recognizes five countries as nuclear-weapon states: the United States, Russia, the United Kingdom, France, and China. These are also the five permanent members of the UN Security Council. The treaty opened for signature in 1968, with the US, UK, and Soviet Union signing first. France, the last of the five, didn’t join until 1992.
The United States was the first country to build and use a nuclear weapon, dropping two bombs on Japan in August 1945. The Soviet Union tested its first device in 1949, the UK in 1952, France in 1960, and China in 1964. Today, the US and Russia hold the largest arsenals by a wide margin, each deploying thousands of warheads across land-based missiles, submarine-launched missiles, and bomber aircraft. This combination of three delivery methods is known as the “nuclear triad,” and both countries maintain all three legs. The US currently fields Minuteman III intercontinental ballistic missiles, 14 Ohio-class submarines carrying Trident II missiles, and B-52 and B-2 bombers. Russia operates a comparable triad.
The UK and France maintain smaller but fully operational arsenals, with the UK relying primarily on submarine-launched missiles and France operating both submarines and air-launched weapons. China has been expanding and modernizing its arsenal in recent years, with estimates suggesting it is on pace to significantly increase its warhead count.
The Four Non-Treaty Nuclear Powers
India, Pakistan, Israel, and North Korea all possess nuclear weapons but sit outside the NPT framework. India, Pakistan, and Israel never signed the treaty. North Korea joined as a non-nuclear state but announced its withdrawal in 2003, a move other NPT members have not legally recognized.
India conducted its first nuclear test in 1974 and a series of underground tests in 1998. Pakistan responded with its own tests just weeks later. Both countries have continued developing their arsenals and delivery systems, and they remain the only two nuclear-armed states that share a contested border and have fought multiple wars against each other.
Israel maintains a unique position through what analysts call “deliberate ambiguity.” Israeli leaders have repeatedly stated that Israel “will not be the first nation to introduce nuclear weapons in the Middle East” while simultaneously acknowledging that Israel has the knowledge to build them. The country has never officially confirmed or denied possessing warheads, has never conducted a publicly acknowledged nuclear test, and refuses to join the NPT. Despite this, outside estimates based on plutonium production suggest Israel holds roughly 80 to 130 warheads. Its delivery systems include the Jericho ballistic missile series, with the Jericho II having a range of about 1,500 kilometers, and its Shavit space launch vehicle could theoretically be modified to reach intercontinental distances.
North Korea has conducted six nuclear tests, the most recent in 2017, and has developed intercontinental ballistic missiles capable of reaching the continental United States. Its Hwasong-18, a solid-fuel ICBM with an estimated range of 15,000 kilometers, was tested three times in 2023. Official North Korean reporting suggests the missile is now considered operationally deployed. The country’s exact warhead count is uncertain, with estimates ranging from 30 to 60.
Countries That Gave Up Nuclear Weapons
Several countries once had nuclear weapons on their soil and chose to give them up. The most notable case is Ukraine, which inherited roughly 1,900 strategic warheads when the Soviet Union collapsed in 1991. By June 1996, Ukraine had transferred its last nuclear warhead back to Russia in exchange for economic aid and security assurances. The last nuclear delivery vehicle on Ukrainian soil was eliminated in 2001. Belarus and Kazakhstan followed similar paths, returning Soviet-era warheads to Russia in the 1990s.
South Africa is the only country to have independently built nuclear weapons and then voluntarily dismantled them. It had assembled six warheads by the late 1980s and destroyed them all before joining the NPT in 1991.
NATO Nuclear Sharing
Five non-nuclear NATO countries host American nuclear weapons on their territory under a program called nuclear sharing: Belgium, Germany, Italy, the Netherlands, and Turkey. As of recent estimates, about 100 US-owned warheads are stored across six bases in these countries, including Kleine Brogel in Belgium, Büchel in Germany, Aviano and Ghedi in Italy, Volkel in the Netherlands, and Incirlik in Turkey. In a conflict, pilots from these host nations could deliver the weapons using their own aircraft, though the warheads remain under American control at all times during peacetime.
Iran’s Nuclear Status
Iran does not have a nuclear weapon, but it has moved closer to the technical capability to build one than any other non-nuclear state. Iran is enriching uranium to 60% purity, far beyond what civilian power reactors require (3 to 5%) and closer to the 90% threshold used in weapons. As of May 2025, Iran had stockpiled over 408 kilograms of uranium enriched to 60%, a figure the International Atomic Energy Agency has called a matter of “serious concern.” The IAEA noted that Iran is the only non-nuclear-weapon state producing such highly enriched material. Iran has also blocked international inspectors from verifying certain weapons-related activities since 2021.
Arms Control Between the US and Russia
The largest two arsenals are governed by the New START treaty, which limits the United States and Russia to 1,550 deployed strategic warheads each. Both countries extended the treaty through February 4, 2026, and the US has assessed annually that Russia was in compliance with its obligations. However, Russia suspended its participation in the treaty’s inspection provisions in 2023, and no successor agreement is currently in place. What happens after the treaty expires in 2026 remains one of the most consequential open questions in nuclear security.