Ohm's law states V = I × R. From this you can also derive I = V / R and R = V / I.

How is power related to Ohm's law?

Electrical power is P = V × I. Using Ohm's law you can also write P = I²R or P = V²/R.

When do I use this calculator?

Use it for quick circuit estimates, troubleshooting, and validating measured voltage/current/resistance values.

Specific conversion page with reference context, calculator, and nearby values.

120 V / 20 ohm converts to

6 A

Use this as a quick reference for Ohm's Law Calculator.

Input: 120 V / 20 ohm

Output: 6 A

voltage: 120 | resistance: 20 | powerW: 720

Pick what to solve for, then provide the required known values.

Calculated Result

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