Electricity in Thailand is 220 volts at 50hz which is compatible with devices sold in many countries. If you are coming from a country that is not compatible then you will need a voltage converter. Even if you do not need a voltage converter you will probably require plug adapters.
Similarly, it is asked, what is the difference between a transformer and a converter?
Converters and transformers both step up or down the voltage, but there is a difference in use between them. Converters should be used only with “electric” products. Electric products are simple heating devices or have mechanical motors. Examples are hair dryers, steam irons, shavers, toothbrushes or small fans.
Do I need a voltage converter to charge my Iphone in Europe?
Yes, you can use the simple adapter. If you read the tiny fine print on the plug end you see "110-240V 50-60Hz" which means it will work on most common electrical systems around the world without a transformer. Yes, it is perfectly safe to use a simple adapter for EU. You do not need additional transformers.