Ohm's Law Calculator

Enter any two values to calculate the other two instantly.

Voltage (V)

Current (A)

Resistance (Ω)

Power (W)

Enter any 2 of the 4 values above

Calculated values — Calculated from: V+I

Voltage

120

Current

5

Resistance

24

Power

600

Key Formulas

V = I × R

I = V / R

R = V / I

P = V × I

P = I² × R

P = V² / R

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Ohm's Law for 120V and 5A

Given a voltage of V = 120 V and a current of I = 5 A, Ohm's Law (V = I × R) gives a resistance of R = V / I = 120 / 5 = 24 Ω.

The corresponding power dissipation is P = V × I = 120 × 5 = 600 W.

Try other combinations of V, I, R, and P with our Ohm's Law Calculator.