Ohm's Law
Solve voltage, current or resistance — with power — from the other two.
Enter values
V
A
Ω
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Step by step
The formula
V = I × R; P = V × I
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Frequently asked questions
Which two values do I need?+
Any two of voltage, current and resistance determine the third (V = I × R). Pick what to solve for and only the other two fields are read; power (P = V × I) is shown alongside.
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