Typical Dominican Republic plug – US Type with ground, some places use only two hole plugs without the ground:
Electricity in the Dominican Republic operates at 110 Volts/60 HZ that is the same as in the United States. The plugs are also the same as in the US. So, converters are not necessary for Americans, Canadians.
Europeans will need convertor from their country to the US plugs.
Many electronic devices now operate in range 110V till 240V, so you usually just need a plug and not actual convertor that changes 110V to 220V etc.
Capture: Typical travel surge protector
Because voltage irregularities are common in the country it is important that any more expensive devices and appliances have surge protection.