Voltage Converter
Free online electrical unit converter.
Convert between all electrical units instantly with accurate results, formulas, and reference tables.
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Frequently Asked Questions
Common questions about the Voltage Converter
Common conversions: 120V↔240V, 110V↔220V, volts to millivolts/kilovolts. Step-up or step-down.
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Sources & References
International System of Units (SI): electric current, voltage and resistance
Electric current, voltage and resistance is measured in the ampere (A), volt (V) and ohm (Ω). Conversions between SI and other units use exact, internationally agreed factors maintained by NIST.
International System of Units (SI)
Authoritative definitions for electric current, voltage and resistance, from the BIPM SI Brochure (9th edition), the defining reference for the SI.