Electric Current Conversion Calculator
Written by Thierno Sadou Diallo, formula verified per our methodology • Last checked on 9/10/2026
To convert an electric current, it is reduced to amperes (A), then converted into the desired unit. Example: a current of 500 mA equals 0.5 A.
Explanation
The ampere (A), the SI unit of electric current, measures the flow of electric charge through a conductor. Its prefixes follow the same decimal rules as the other electrical units: the microampere and milliampere are used for small currents (digital electronics, an LED, a sensor), the ampere for common domestic uses (a phone charger, a 16 A circuit breaker), and the kiloampere for very high currents such as an industrial short-circuit current or a lightning strike. This calculator converts between these scales using the ampere as the pivot unit. To calculate a current from voltage and resistance rather than converting a known value, see our Ohm's law calculator, and for the related quantity, our voltage conversion calculator.
Example: a current of 500 mA
Inputs
Value: 500. Starting unit: mA. Target unit: A.
Calculation
The "milli" prefix means 0.001: to go from milliamperes to amperes, multiply by 0.001. 500 × 0.001 = 0.5 A.
Result
A current of 500 mA equals 0.5 A.
Frequently asked questions
What is the difference between current and voltage?
Current (in amperes) measures the flow of electric charges through a conductor, while voltage (in volts) measures the potential difference that pushes those charges to flow — see our voltage conversion calculator for the other quantity.
Why is a domestic circuit breaker rated in amperes?
A circuit breaker (often 16 A or 20 A for a standard domestic circuit) automatically cuts the circuit if the current exceeds that threshold, protecting the wiring against overheating from an excessive current.
How do you calculate a current rather than convert it?
This calculator converts a known current value between units; to calculate a current from other electrical quantities (voltage and resistance), use instead our Ohm's law calculator, which directly applies the relationship I = V ÷ R.
Do other electrical quantities also have their own prefixes to convert?
Yes: see our electrical resistance conversion calculator for resistance, each with its usual orders of magnitude depending on the component involved.