Voltage regulators and power conditioners come in either 50 or 60 Hertz (frequency) or in some smaller units dual frequency (both 50 and 60 Hz). The USA, Canada, Mexico, Puerto Rico, South Korea, Taiwan and the Philippines use 60 Hz. Europe, most of Asia and Africa and Australia use 50 Hz. Latin American and Caribbean countries are a mix of 50 and 60 Hz, depending on the country. Some countries such as Japan, Saudi Arabia and Brazil use both.

In most developed countries, electric frequency deviates very little from the standard. A deviation one-half percent would be considered unusual. For this reason the operating frequency of the power conditioner is generally not an issue. In countries with very unstable electrical systems or when using a power conditioner behind a generator, frequency of operation can become an issue. Most power conditioners do not correct frequency. If frequency correction is required, it would normally be done separately ahead of the power conditioner.