Ohm's Law

Use Ohm’s law to calculate resistance from voltage and current.

How this calculator works

Enter the values for value, rate (%) and review the units before calculating.

Formula / method

R = V ÷ I

Worked example

12 V across 2 A gives a resistance of 6 Ω.

Assumptions and limitations

The circuit is modeled as a steady linear DC relationship.

Real components can heat, saturate or vary with frequency and operating point.