Last year China carried out more missile launches, for testing and development, than the rest of the world combined. China is a nuclear power that is not particularly concerned about boasting of how many nukes and delivery systems it has. China is also better able to keep secret most of its missiles tests. Rather than firing missiles out to sea, where they have to issue a warning to ships to avoid the area where the warheads will land, China conducts most of its missile tests at an inland test site near the Gobi Desert. Plenty of open space and far from prying eyes. The only nation with a good idea of how many Chinese missile tests there are each year is the United States, which has a worldwide network of early-warning satellites that can spot the heat generated from a ballistic missile launch anywhere on the planet. The U.S. will not disclose how many Chinese missiles they have spotted each year but in 2018 speech an American official commented that China launched more missiles each year than the rest of the world combined. Similar comments since then indicate that China is currently launching more than a hundred missiles a year, most of them at the remote inland test site in the northwest. The Americans also have a network of electronic monitoring satellites that can collect telemetry data. This is what the test warhead transmits back to earth about how the missile is performing. This data is encrypted and the U.S. says even less about how many of these signals it captures and decrypts.
The U.S. is very interested in finding out details of new Chinese missiles because some will have capabilities that the U.S. and Russia gave up for several decades because of the INF (Intermediate-Range Nuclear Forces) disarmament treaty signed near the end of the Cold War. The U.S. did admit that the main reason for not renewing the UNF Treaty with Russia in 2019 was not just Russian cheating but also because China never signed the INF treaty and is free to develop the ballistic and cruise missiles with ranges of 500 to 5,500 kilometers the INF forbids.
China also pretends it is unconcerned about who the target is. In 2009, China announced that its nuclear-armed ballistic missiles were not aimed at anyone. Like most countries, China has long refused to say who its nuclear-armed missiles are aimed at. Most of those missiles only have enough range to hit Russia, or India, or other nearby nations. For a long time, most were very definitely aimed at Russia, which had rocky relations with China from the 1960s to the 1990s. But after the Soviet Union dissolved in 1991, the new, much smaller, Russia became much friendlier with the wealthier (more capitalist, but still run by communists) China. Relations between China and India also warmed up then went into a deep freeze.
China is believed to have 300-400 nuclear warheads, most of them installed on ballistic missiles. Fewer than a hundred of these missiles can reach the United States. These include the older (and about to be retired) DF-5, plus the newer DF-31A and DF-41.
Few Chinese ballistic missiles lacking intercontinental range are armed with nuclear warheads as the Chinese strategy is to use lots of ballistic missiles armed with high-explosive warheads. In the early stages of a war over a thousand of these shorter range missiles can overwhelm air and ballistic missile defense systems to damage or destroy airbases, warships headquarters and other key targets. For over a decade China has had over a thousand of these missiles based within range of Taiwan. Many of these missiles are mobile and a large number could be moved to threaten Japan or South Korea.
China is believed to have about 2,000 ballistic missiles, most of them short (under a thousand kilometers) range plus over 300 cruise missiles. China is developing more cruise missiles concentrating, as is the United States, on stealth and additional capabilities. China is also developing and deploying many new missiles. In fact, China has more types of ballistic missiles, at least 40, than any other nation. China also invests heavily in its new missile technologies, like its hypersonic glide missile, the DF-ZF.
China is known to have a large number of ICBM and shorter range IRBM missiles. These include about twenty DF-41 (range of 14,000 kilometers), about eighty DF-31 - 50 (8,000 kilometers), thirty DF-5 - ( 14,000 kilometers), thirty DF-4 (5,500 kilometers), eighty DF-26 (4,000 kilometers), fifty DF-21D Anti-Ship Ballistic Missile –(1,500 kilometers), 300 DF-21 (1,700 kilometers), fifty DF-16 (800 kilometers), 300 DF-15B (800 kilometers), 500 DF-15A (900 kilometers), 1,200 DF-11A (700 kilometers). The only cruise missile is the CJ-10A (1,500 kilometers). There are several hundred other short-range ballistic missiles as well, some of them still in development.
Since the 1990s China has always had a few active DF-5 ICBMs. For a long time, these were their only missiles that could reach the United States. But the U.S. has since installed 18 ICBM interceptor missile systems in Alaska. There are to deal with North Korean missiles but could also destroy most Chinese missiles headed for the western United States. Thus it makes sense for China to simply say that it is not aiming any of its missiles at anyone. Modern guidance systems can be quickly (in less than an hour) programmed for a new target, so it doesn't really matter that, normally, the missiles have no target information in them. The DF-5s, moreover, are liquid-fueled, and the considerable activity required to ready them for launch can be detected by spy satellites.
The DF-5s have been largely replaced by solid fuel DF-41s. These missiles can be moved, erected and launched from a special truck. With a 15,000 kilometer range, they can reach all of the United States. The third stage contains up to twelve warheads, each with an explosive yield of about 100 KT.
India is of growing concern to China, but there are shorter range ballistic missiles, like the DF-21, to deal with that threat. The Chinese introduced the DF-21 in 1999 and now has over a hundred in service. Many have non-nuclear warheads. This missile has a range of over 1,800 kilometers and can haul a 300 kiloton nuclear warhead. It's a two-stage, 15 ton, solid-fuel rocket. Launched from Tibet, the DF-21 can reach most major targets in India.
Back in 2006 China put the larger DF-31 into service. Sort of. This was China's first solid-fuel ICBM (with a range of over 8,000 kilometers) and roughly equivalent to the U.S. Minuteman I of the 1960s. The DF-31 weighs about 46 tons and is 20 meters (62 feet) long and 2.25 meters (7 feet) in diameter. It was designed for use on submarines, land silos and mobile launchers (which would halt at those "parking lots in the middle of nowhere" visible in satellite pictures of Qinghai province). The DF-31 has been shown stored in a TEL (transporter, erector, launcher) vehicle. Driving these vehicles along special highways in remote areas provides more protection from counterattacks than using a reinforced silo. Later, the improved DF-13A appeared, with multiple warheads and more range (up to 12,000 kilometers, which could cover all the United States.)
The DF-31 was in development for over twenty years and only had its first successful launch in 1999. It's now believed to have a reliable and accurate guidance system, as well as a third stage that carries three 50 kiloton warheads. DF-31s are in service, along with DF-31As and most of these appear to be aimed at European Russia.
Then there is a submarine-launched missile the JL (Julang) 2 SLBM (Sea Launched Ballistic Missile). This missile has had a lot of problems as have the SSBNs (ballistic missile carrying nuclear subs) that carry them. The 42 ton JL-2 has a range of 8,000 kilometers and would enable China to aim missiles at any target in the United States from a 094 class SSBN cruising off Hawaii or Alaska. Each 094 boat can carry twelve of these missiles, which are naval versions of the existing land based 42 ton DF-31 ICBM. The JL-2 was supposed to have entered service 2015, but kept failing test launches. China decided that JL-2 was reliable enough and ordered it installed in four SLBMs. No Chinese SSBN has ever gone on a combat cruise, because these boats, as well as the SLBMs, have been very unreliable.
About two thirds of Chinese nuclear warheads are believed to be in missile warheads, most of them DF-21s. Normally, these warheads are stored separately and mated to the missiles only for actual use, or the occasional training exercise.