Calculate electrical current from voltage and resistance, power and voltage, or power and resistance. This current calculator estimates amps, milliamps, microamps, voltage, resistance, and power using Ohm's Law and electrical power formulas.
Voltage and resistance:
Enter volts and ohms. The calculator uses I = V ÷ R.
Power and voltage:
Enter watts and volts. The calculator uses I = P ÷ V.
Power and resistance:
Enter watts and ohms. The calculator uses I = √(P ÷ R).
A current calculator helps estimate amps when you know voltage, resistance, or power.
It can help with electronics projects, resistor planning, wire sizing estimates, battery loads, DC circuits, appliance loads, LED circuits, and basic electrical troubleshooting.
Your result shows estimated current, milliamps, microamps, voltage, resistance, power, the formula used, current category, scenario comparisons, and a calculation summary based on the values entered.
Use I = V ÷ R when you know voltage and resistance. Divide volts by ohms to get amps.
Use I = P ÷ V. Divide watts by volts to estimate current in amps.
Use I = √(P ÷ R). Divide watts by ohms, then take the square root.
No. Current is electrical flow, while voltage is electrical pressure. Both are connected through Ohm's Law.