Electricity
Voltage / Current / Resistance Calculator
Apply Ohm's Law to calculate voltage, current, or resistance. Includes power calculation for complete electrical circuit analysis.
Apply Ohm's Law to calculate voltage, current, or resistance. Includes power calculation for complete electrical circuit analysis.
Ohm's Law Calculator
The Voltage, Current, and Resistance Calculator is based on Ohm's Law (V = IR), one of the most fundamental principles in electrical engineering. This law describes the relationship between voltage, current, and resistance in electrical circuits.
Whether you're designing circuits, troubleshooting electrical systems, or calculating LED resistor values, this tool provides quick and accurate results. It also calculates power dissipation (P = VI), making it a complete solution for basic electrical analysis.
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Cover what you want to find, the remaining shows the formula
Ohm's Law states that the current through a conductor is directly proportional to the voltage and inversely proportional to resistance.
V = I × R
I = V / R
R = V / I
P = V × I = I²R = V²/R
Ohm's Law applies to "ohmic" materials where resistance is constant. Some materials (diodes, transistors) have non-linear behavior.