In Tibet, the power sockets are of types A, C, and I. The standard voltage is 220 V and the standard frequency is 50 Hz. If the standard voltage in your country is between 220 – 240 V (as in the UK, Europe, Australia, and most of Asia and Africa) you can easily use your electric appliances it, Tibet.
However, if the standard voltage in your country is in the range of 100 V – 127 V (as in the US, Canada, and most South American countries), you need a voltage converter in Tibet. You can bring your own voltage converter as you might not find them in Tibetan stores. Alternately, you can also buy them in Kathmandu (if traveling to Tibet via Nepal).
If the label in your electric appliance states ‘INPUT: 100-240V, 50/60 Hz’ the appliance can be used in all countries of the world. This is common for chargers of tablets/laptops, photo cameras, cell phones, toothbrushes, etc.