Ohm's law free online calculator

Enter 2 values to get the other values and press the Calculate button:

Resistance (R):
Current (I):
Voltage (V):
Power (P):

AC Ohm's law calculator

Enter 2 values of magnitude+phase angle to get the other values and press the Calculate button:

Impedance (Z):
°  = 
Current (I):
°    
Voltage (V):
°    
Power (S):
°  = 

Ohm's law formula

The voltage V in volts (V) is equal to the current I in amps (A) times the resistance R in ohms (Ω):

V(V) = I(A) × R(Ω)

The power P in watts (W) is equal to the voltage V in volts (V) times the current I in amps (A):

P(W) = V(V) × I(A)

AC Ohm's law formula

The voltage V in volts (V) is eqaul to the current I in amps (A) times the impedance Z in ohms (Ω):

V(V) = I(A) × Z(Ω) = (|I|×|Z|) ∠ (θI + θZ)

The complex power S in volt-amps (VA) is equal to the voltage V in volts (V) times the current I in amps (A):

S(VA) = V(V) × I(A) = (|V|×|I|) ∠ (θV - θI)

Ohm's law »


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