Enter any 2 values then click "Calculate". The unknown values will be calculated.

Voltage		millivolts	volts	kilovolts
Current		milliamps	amps	kiloamps
Resistance		milliohms	ohms	kilohms
Power		milliwatts	watts	kilowatts

Ohm's Law defines the relationship between power, voltage, current, and resistance. The various possible formulas for Ohm's law are as follows.

Where
P = power in watts
E = voltage in volts
I = current in amps
R = resistance in ohms

P = E²/R
P = I² * R
P = E * I

E = sqrt(P * R)
E = P/I
E = I * R

I = E/R
I = P/E
I = sqrt(P/R)

R = E/I
R = E²/P
R = P/I²