Enter any two of voltage (V), current (I), resistance (R), or power (P) — the other two are solved from Ohm's law (V = I·R) and the power formula (P = V·I). Leave the fields you want calculated blank.
Inputs
Enter any two values.
Results (SI base units)
Voltage
—
Current
—
Resistance
—
Power
—
Formulas used
Ohm's law: V = I · R
Power: P = V · I = I²·R = V²/R
Derived: I = V/R, R = V/I, V = √(P·R), I = √(P/R)
Results are rounded to 6 significant figures. Values use SI units internally (V, A, Ω, W) but you can input with any prefix.