Ohm's Law Calculator
Fill in what you know — solve voltage, current, resistance, and power.
Enter any two known values and leave the rest blank to solve. Uses V = IR and P = VI / I²R / V²/R.
Voltage
12 V
Current
0.5 A
Resistance
24 Ω
Power
6 W
What is this tool?
Ohm's law relates voltage (V), current (I), and resistance (R) as V = I·R. Power identities P = V·I, P = I²R, and P = V²/R connect electrical power to the same triangle. Leave unknown fields blank and enter at least two known values.
How to use it
- Enter at least two of V, I, R, or P.
- Read the solved set of values.
- Cross-check against your schematic and component ratings before building.
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