How to use it
- Choose the value you want to calculate.
- Enter the other two requested values in volts, amps or ohms.
- Calculate and review the result and formula.
Ohm's Law Calculator
Calculate voltage, current or resistance from the other two electrical values.
Important: This calculator is for educational and estimation purposes only. It is not electrical safety, installation, engineering, or code-compliance advice. Always consult a qualified electrician or engineer for real-world electrical work.
About the Ohm's Law Calculator
Ohm's law relates voltage, current and resistance in a simplified electrical relationship.
How it works
The calculator rearranges V = I × R as I = V ÷ R or R = V ÷ I for the selected mode.
Example
A current of 2 A through 10 Ω corresponds to 20 V in the idealized Ohm's law relationship.
Notes
Real components may be nonlinear or change with temperature. Use this page for education and estimates, not circuit or safety decisions.