Ohm's Law Calculator
Solve for voltage, current or resistance, with power. The result updates as you type, with the working underneath so you can check it.
Your details
Result
Voltage
12 V
- Power
- 6 W
Good to know: V = I × R
Please note: For study and planning. Check calculations independently before using results with chemicals, electricity, pressure or machinery, and follow safety data sheets, manufacturer instructions and local regulations.
About this tool
Formula
V = I × R
Questions people ask
What does Ohm's law say?
Current through a conductor is proportional to the voltage across it: V = IR. Power is then P = VI.
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How we calculate this
We use the standard published formula or definition for this calculation, and we show the working so you can check it.
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