Ohm’s Law Calculator
Calculate voltage, current, resistance and electrical power using Ohm’s law.
How to Use the Ohm’s Law Calculator
Enter any two of voltage, current and resistance. The calculator solves the missing electrical value and then calculates power.
Practical Example
A 12 V circuit with 6 Ω resistance draws 2 A and uses 24 W.
Factors That Affect the Result
Real circuits can include temperature effects, component tolerances, AC behavior and safety limits that simple Ohm’s law does not model.
Frequently Asked Questions
What values do I need?
Enter exactly two of voltage, current and resistance.
Does it calculate watts?
Yes.
Is it suitable for AC circuits?
Only for simple resistive cases; AC impedance can require additional calculations.
Formula and Practical Context
Ohm’s law relates voltage, current and resistance as V = IR, while electrical power can be written P = VI and equivalent forms derived from Ohm’s law. The simple relationships assume appropriate steady-state conditions; real components can change resistance with temperature or operating point.