China: About 250 total warheads.
France: 290 deployed warheads.
Russia: According to the September 2014 New START numbers, Russia has 1,643 strategic warheads deployed on 528 ICBMs, SLBMs, and strategic bombers [1]. The Federation of American Scientists estimates Russia has several thousand nondeployed strategic warheads and approximately 2,000 tactical nuclear warheads. An additional 3,700 are awaiting dismantlement.
United Kingdom: About 120 strategic warheads, of which no more than 40 are deployed at sea at any given time. The total stockpile is up to 225 weapons.
United States: According to the September 2014 New START declaration, the United States has 1,642 strategic nuclear warheads deployed on 794 ICBMs, SLBMs, and strategic bombers [1]. The Federation of American Scientists estimates that the United States’ nondeployed strategic arsenal is approximately 2,800 warheads and the U.S. tactical nuclear arsenal numbers 500 warheads. In total, the U.S. has about 4,800 nuclear warheads [2], including tactical, strategic, and nondeployed weapons. Additional warheads are retired and await dismantlement.
Non-NPT Nuclear Weapons Possessors:
Three states—India, Israel, and Pakistan—never joined the NPT and are known to possess nuclear weapons. Claiming its nuclear program was for peaceful purposes, India first tested a nuclear explosive device in 1974. That test spurred Pakistan to ramp up work on its secret nuclear weapons program. India and Pakistan both publicly demonstrated their nuclear weapon capabilities with a round of tit-for-tat nuclear tests in May 1998. Israel has not publicly conducted a nuclear test, does not admit to or deny having nuclear weapons, and states that it will not be the first to introduce nuclear weapons in the Middle East. Nevertheless, Israel is universally believed to possess nuclear arms, although it is unclear how many weapons Israel possesses. The following arsenal estimates are based on the amount of fissile material—highly enriched uranium and plutonium—that each of the states is estimated to have produced. Fissile material is the key element for making nuclear weapons. India and Israel are believed to use plutonium in their weapons, while Pakistan is thought to use highly enriched uranium.
India: Between 90-110 nuclear warheads.
Israel: Between 80-100 nuclear warheads, with fissile material for up to 200.
Pakistan: Between 100 to 120 nuclear warheads.
States of Immediate Proliferation Concern:
Iran is pursuing a uranium-enrichment program and other projects that could provide it with the capability to produce bomb-grade fissile material and develop nuclear weapons within the next several years. In contrast, North Korea has the material to produce a small number of nuclear weapons, announced its withdrawal from the NPT, and tested nuclear devices. Uncertainty persists about how many additional nuclear devices North Korea has assembled beyond those it has tested. In September 2005, Pyongyang “committed to abandoning all nuclear weapons and existing nuclear programs.”
Iran: No known weapons or sufficient fissile material stockpiles to build weapons. However, the International Atomic Energy Agency (IAEA), the institution charged with verifying that states are not illicitly building nuclear weapons, concluded in 2003 that Iran had undertaken covert nuclear activities to establish the capacity to indigenously produce fissile material. The IAEA is continuing its investigation and monitoring of Tehran’s nuclear program.
North Korea: Has separated enough plutonium for roughly 6-8 nuclear warheads. North Korea unveiled a centrifuge facility in 2010, buts ability to produce highly-enriched uranium for weapons remains unclear. In August 2013, North Korea restarted the heavy-water reactor it used to extract plutonium in the past for its nuclear warheads, although operation of the reactor since August has not been constant. Experts estimate it will be about 18 months before the first new bomb-ready plutonium will be separated from the spent fuel.
Syria: In September 2007, Israel conducted an airstrike on what U.S. officials have alleged was the construction site of a nuclear research reactor similar to North Korea’s Yongbyon reactor. Intelligence officials briefed members of congress on the airstrike eight months later in April 2008, discussing the evidence leading to their judgment that the site was an undeclared nuclear reactor. While the extent of Syrian-North Korean nuclear cooperation is unclear, it is believed to have begun in 1997. Subsequent IAEA investigations into the U.S. claims uncovered traces of undeclared man-made uranium particles at both the site of the destroyed facility and Syria’s declared research reactor. Syria has failed to provide adequate cooperation to the IAEA in order to clarify the nature of the destroyed facility and procurement efforts that could be related to a nuclear program.