Ohm’s Law Calculator — Calculate Voltage, Current, Resistance

Ohm’s Law Calculator

Calculate voltage, current, resistance, and power using Ohm’s Law. Understand the relationship between electrical parameters with this free calculator.

Step 1: Enter Known Values

Ohm’s Law Formula

V = I × R (Voltage = Current × Resistance)
P = V × I (Power = Voltage × Current)
Enter any two values to calculate the other two.

Step 2: Calculation Options

About 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.

Ohm’s Law Calculation Results

Results Summary
Ohm’s Law Formula
Electrical Examples

Calculated Value

12 V
Voltage Calculation
Voltage (V)
12 V
Current (I)
0.5 A
Resistance (R)
24 Ω
Power (P)
6 W

Ohm’s Law Formulas

Parameter Formula Unit Description
Voltage (V) V = I × R Volts (V) Electrical potential difference
Current (I) I = V ÷ R Amperes (A) Flow of electric charge
Resistance (R) R = V ÷ I Ohms (Ω) Opposition to current flow
Power (P) P = V × I Watts (W) Rate of energy transfer
Power (alternative) P = I² × R Watts (W) Power from current and resistance
Power (alternative) P = V² ÷ R Watts (W) Power from voltage and resistance

Understanding Ohm’s Law

Ohm’s Law is fundamental to understanding electrical circuits. It describes how voltage, current, and resistance are related. If you know any two of these values, you can calculate the third using the appropriate formula.

Common Electrical Examples

Application Voltage Current Resistance Power

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