Layover transit visa

The first and the most important detail is that when traveling through one country, China included, you have a right to a transit that is visa free, but it also implies that you will not leave the transit area. However, Chinese authorities have implemented a temporary entry permit that is granted to those traveling with small children, disabled passengers and those having a very long layovers, especially during the nighttime. This permit, by its definition, is not a passenger's right, but more like a bonus that is offered on case by case basis. In other words the issuing of the permit remains in absolute jurisdiction and discretionary decision of the Chinese immigration authorities.

Since you have 12 hours long layover, I would say that your chances are very good, but definitely not with 100% certainty. There is nobody that could guarantee 100% certainty when we come to this option.

In any case, the first thing that you will do upon landing is to approach 24 hour visa free transit counter where you will apply for a temporary entry permit by presenting your flight tickets. It is advisable to have all those details printed out. This application is free of any charge. After a short check, you will be hopefully granted a permit and after that you will head to the immigration. When you have cleared the immigration you will proceed to the city to enjoy your free time on your own. Have a nice journey.