Ohm's Law Calculator
Enter any two of voltage, current, and resistance to solve for the third using Ohm's Law.
Calculate
Enter your values below.
Result
Voltage (V)
0
Current (A)
0
Resistance (Ω)
0
Formula used
V = I × R
Example: 2 A through 6 Ω → voltage = 12 V.
How to use this calculator
- Enter Voltage (V), Current (A), Resistance (Ω).
- Press Calculate to see your result instantly.
FAQ
Frequently asked questions
How many values do I need to enter?
Exactly two — leave the third field blank and it will be calculated.
What is Ohm's Law?
A fundamental electrical relationship: Voltage = Current × Resistance.
What if I fill in all three or leave two blank?
The calculator needs exactly two known values to solve for the third — please adjust your inputs.
What units does this use?
Volts (V), amps (A), and ohms (Ω) — the standard SI electrical units.