The world’s nuclear powers have nearly 10,000 nuclear warheads in their arsenals. These weapons have the capacity to kill millions directly and through their impact on agriculture have likely the potential to kill billions.

Nuclear weapons technology was developed during the 1930s and 1940s. The first nuclear weapons were detonated over Hiroshima and Nagasaki in August 1945. Since then, controlling the proliferation of nuclear weapons has been an important issue in international relations.

On this page you find several charts with the most important metrics. For an overview of the risks from nuclear weapons – and how they can be reduced – read the following essay:

Stockpiles of nuclear weapons

The states with nuclear capabilities now includes the United States, Russia, United Kingdom, France, China, India, Pakistan, Israel and North Korea. One way of quantifying the proliferation of nuclear weapons is to look at the stockpiles countries have. The total inventories of nuclear warheads are even larger, as stockpiles do not include retired warheads queued for dismantlement.

This chart shows that the total number of stockpiled nuclear weapons in the world peaked in 1986. It should be remembered that the destructive power of nuclear warheads differs very significantly.

Nuclear weapons tests

This interactive chart shows the number of nuclear weapons tests conducted since 1945.

We can see that the Cold War was a very active period of nuclear weapons development. Although nuclear weapons were only ever used in warfare during the Second World War, there have been many tests conducted since then.

Nuclear Powers

It is a common misconception that more and more nations are exploring and developing nuclear weapons since the Second World War. As the graph demonstrates, there have been peaks in nuclear weapon development in the past few decades. By the late 1980s, the number of nations developing nuclear weapons started falling and has remained steady since the mid-1990s.

The names in the graph represent nations developing weapons, and countries marked with “-” represent the year in which development in that country ceased.

Non-nuclear states that started and stopped exploring nuclear weapons, 1945-2010 – Pinker1
Nonnuclear States that Started and Stopped Exploring Nuclear Weapons, 1945–2010 - Pinker0