Ohm's law

How the calculation works

Calculate voltage, current, resistance and power from two known values. The tool converts the form units and presents the result using readable engineering notation.

V = I × R; P = V × I

Example

For 12 V and 240 Ω, current is 0.05 A and power is 0.6 W.

How to interpret the result

• Use this calculator when two quantities in a resistive circuit are known and one is missing.
• Power helps verify resistor and supply margin.
• Ohm’s law does not directly model nonlinear devices such as LEDs or transistors.

Limitations and safe use

The result uses a simplified model. Check tolerance, temperature, absolute ratings and the component datasheet.