Most chargers are suitable for use on voltages ranging from 100 volts to 250 volts.
Get out the magnifying glass. The rating is usually printed on the charger. If you know someone with a 220/100 transformer you could test them here before leaving.
Have a safe trip and a Taiwan Beer for me (good stuff).
I believe that Taiwan uses the same voltage and plugs as the US (type A and B) and they use ~110V. The need for an adaptor will depend on the plug of the device.
Always best to have a universal adaptor while traveling in case you have a layover in a country with different plugs.