In Thailand the standard voltage is 220 V. The standard frequency is 50 Hz. The power sockets that are used are of type A / B / C. Below you find pictures of these power sockets and corresponding plugs. And we provide more information about the voltage and frequency.
You can use your electric appliances in Thailand, if the standard voltage in your country is in between 220V - 240V (as in the UK, Europe, Australia and most of Asia and Africa). Manufacturers take these small deviations into account. If the standard voltage in your country is in the range of 100V - 127V (as in the US, Canada and most South American countries), you need a power (voltage) converter. To be sure, check the label on the appliance. If it states 'INPUT: 100-240V, 50/60 Hz', it can be used in all countries of the world (like chargers for tablets/laptops, photo cameras, cell phones, toothbrushes).
Source: http://www.power-plugs-sockets.com/thailand/