Ohm's Law Calculator
Use voltage and resistance to calculate current, electrical power and conductance for a simple resistive circuit. It is a quick check for DC circuits and idealized AC resistive loads.
Current2 A
Power24 W
Conductance0.166667 S
Assumes a purely resistive element. AC circuits containing inductance or capacitance require impedance rather than resistance alone.
How this tool works
Current I = V ÷ R. Power P = V × I = V² ÷ R. Conductance G = 1 ÷ R.
Example
Applying 12 V across a 6 Ω resistance produces 2 A and 24 W of power.
Common questions
Does this handle reactance?
No. This version assumes purely resistive behavior. AC impedance with inductance or capacitance requires complex impedance calculations.
Can resistance be zero?
A zero-ohm ideal source would imply unbounded current, so the calculator requires resistance above zero.