Ohm's Law Calculator

Blog post description.

Wiratama

11/15/20251 min read

Ohm’s Law – Definition

Ohm’s Law describes the relationship between voltage (V), current (I), and resistance (R) in an electrical circuit. It states that the current flowing through a conductor is directly proportional to the voltage applied and inversely proportional to the resistance. This fundamental principle is the basis for analyzing nearly all DC and low-frequency electrical systems.

Background Theory

Ohm’s Law is expressed as:

Where:

  • V = voltage (volts)

  • I = current (amperes)

  • R = resistance (ohms)

In addition to Ohm’s law, power calculations follow the power law:

These two equations allow you to compute any unknown electrical quantity when the others are known. They are widely used in designing electrical circuits, selecting components, troubleshooting faults, and evaluating power consumption.

How This Calculator Works

This calculator allows you to solve for any one of the four main variables: Voltage (V), Current (I), Resistance (R), or Power (P).

It works by:

  1. Letting you choose which variable you want to solve for

  2. Accepting the known values (e.g., V & R, or V & I, etc.)

  3. Applying the appropriate Ohm’s Law or Power Law equation

  4. Instantly calculating and displaying the missing value

This tool provides a fast and reliable way to analyze simple circuits for educational, hobbyist, or engineering applications.