Ohm's law calculator

Enter any two of voltage, current, resistance, and power to calculate the other values. Includes formula reference.

How to use

1. Fill in at least two known values.
2. Leave unknown fields empty.
3. Read calculated V, I, R, and P instantly.

Example

Ohm's law calculator

Enter any two of voltage, current, resistance, and power to calculate the other values. Includes formula reference.

When to use

• When you need a quick estimate without spreadsheets.
• When you want privacy — calculations stay on your device.