"The authors calculate that some 125,000 nuclear warheads have been
built since 1945, about 97 percent of them by the United States and the Soviet
Union and Russia. The nine nations with nuclear weapons now possess more than
10,000 nuclear warheads in their military stockpiles, the authors estimate, with
several thousand additional US and Russian retired warheads in storage, awaiting
dismantlement. The nuclear stockpiles of China, as well as Pakistan, India,
Israel, and North Korea, are minuscule in comparison with the US and Russian
arsenals, but more difficult to estimate." (thanks Amir)