Fundamentals
Core electrical concepts: Ohm's Law, voltage, current, and resistance.
Calculators
Ohm's Law Calculator
Enter any two of voltage, current, and resistance to calculate the third, plus power.
Voltage Calculator
Calculate voltage from current and resistance using Ohm's Law (V = I × R).
Current Calculator
Calculate current from voltage and resistance using Ohm's Law (I = V ÷ R).
Resistance Calculator
Calculate resistance from voltage and current using Ohm's Law (R = V ÷ I).
Guides & Examples
Example
Ohm's Law Examples
Worked, step-by-step examples applying Ohm's Law to find voltage, current, and resistance.
Formula
Ohm's Law Formula
The Ohm's Law formula, its variables, and how to rearrange it to solve for voltage, current, or resistance.
Guide
Electrical Fundamentals
An introduction to voltage, current, and resistance, and how Ohm's Law ties them together.