Watts-volts-amps-ohms free online calculator

Watts (W) - volts (V) - amps (A) - ohms (Ω) calculator.

Calculates power / voltage / current / resistance.

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

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

Ohms calculations

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

The resistance R in ohms (Ω) is equal to the squared voltage V in volts (V) divided by the power P in watts (W):

The resistance R in ohms (Ω) is equal to the power P in watts (W) divided by the squared current I in amps (A):

Amps calculations

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

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

The current I in amps (A) is equal to the square root of the power P in watts (W) divided by the resistance R in ohms (Ω):

Volts calculations

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

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

The voltage V in volts (V) is equal to the square root of the power P in watts (W) times the resistance R in ohms (Ω):

Watts calculation

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

The power P in watts (W) is equal to the squared voltage V in volts (V) divided by the resistance R in ohms (Ω):

The power P in watts (W) is equal to the squared current I in amps (A) times the resistance R in ohms (Ω):

Ohm's law »


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