Ohm’s Law Calculator
Calculate voltage, current, resistance, and power instantly with our free Ohm’s Law calculator. Perfect for electrical engineers, students, and hobbyists.
Voltage (V)
Current (I)
Resistance (R)
Power (P)
V = I × R
I = V ÷ R
R = V ÷ I
P = V × I
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Ohm’s Law Calculator FAQs
What is Ohm’s Law?
Ohm’s Law states that the current through a conductor between two points is directly proportional to the voltage across the two points, and inversely proportional to the resistance between them. The formula is V = I × R.
How do I use this calculator?
Simply enter any two known values (voltage, current, resistance, or power) and the calculator will automatically compute the missing values. You can enter values in any field.
What units does this calculator use?
The calculator uses standard units: volts (V) for voltage, amps (A) for current, ohms (Ω) for resistance, and watts (W) for power.
Can I calculate power with this tool?
Yes! Our calculator includes power calculations (P = V × I) in addition to the standard Ohm’s Law formulas.