Use case
This calculator is useful when current and resistance are known and you need the voltage drop across an ideal resistor or simple circuit section.
Example
If current is 2 A and resistance is 6 ohms, voltage is 2 x 6 = 12 V. The same relationship is used to solve simple Ohm's law problems.
Common mistakes
Ohm's law applies to ohmic behavior. Some components, such as LEDs, motors and batteries under load, do not behave like simple fixed resistors.
Limitations
Check component power ratings, heat dissipation and circuit protection before applying results to hardware. This calculator is not an electrical safety approval.
Last reviewed: 2026-05-17