Nuclear weapons worldwide data
This BBC article lists countries with nuclear weapons and how many they have.
Total world nuclear warheads are estimated be 20,000. Many however are not operational.
Only about one quarter or 5,000 of the total are operational. Countries are secretive about how many nuclear weapons they have. Israel officially does not even admit it has any.
The Federation of American Scientists has made estimates of stockpiles of each nuclear country based on information that is available.
Russia has the largest stockpile with 2,430 operational weapons and an estimated 10,000 in all. The U.S. has 1,950 that are operational with a total of 8,500.
In comparison to the U.S. and Russia other countries have relatively few nuclear warheads. France has 290 operational and 300 stockpiled. China is said to have 0 operational but 240 stockpiled.. The UK 160 operational and 225 stockpiled.. Israel has 0 operational but about 80 stockpiled.
Pakistan has 0 operational but between 90 and 110 stockpiled. India also has 0 operational but about 80to 100 stockpiled. The two countries are about equal in stockpiles.
Finally North Korea has 0 operational and less than 10 stockpiled. Obviously there is a huge task ahead if nuclear weapons are to be eliminated. No doubt Russia and the U.S. could both eliminate some of their stockpiles without endangering any power balance.