Dryers typically are on their own circuit breaker. The size of the circuit breaker will also help you determine the voltage of the dryer.
Compact electric dryers and gas-powered standard-size dryers employ 110 volts of electricity to do their job. Standard-size electric dryers, however, need 220 volts of electricity to get your clothing dry. To determine if you have a 110-volt compact dryer, a 110-volt electric-start gas dryer or a 220-volt standard-size electric dryer, check your breaker box or inspect the plug configuration attached to the end of the dryer's electrical cord. The cord is the easiest way to make a determination.
Flip your dryer's breaker to the off position in the breaker box.
Pull the dryer away from the wall so you can see where it is plugged in.
Pull the plug out of the outlet and inspect the plug configuration, using a flashlight. If you find a standard three-prong plug, your dryer is either a 110-volt compact or a 110-volt electric-start gas dryer. If you find a larger three-prong plug, with two of the plugs positioned diagonally, your dryer is a 220-volt dryer.