Science
Ohm's Law Calculator
Solve for voltage, current, or resistance from the other two — plus the resulting power draw.
Inputs
Ohm's Law Calculator
Result
Voltage
12 V
- Voltage
- 12 V
- Current
- 2 A
- Resistance
- 6 Ω
- Power
- 24 W
How it's calculated
V = I × R; P = V × I
Common questions
What is Ohm's law?
Voltage equals current times resistance (V = IR). It describes the linear relationship between the three quantities in a resistive circuit.
How do I calculate power from V and I?
Multiply them: P = V × I. A 12 V circuit drawing 2 A dissipates 24 W of power.
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