Calculate voltage, current, resistance, and power using Ohm's Law. Perfect for electronics students, engineers, and technicians.
V = I × R
I = V ÷ R
R = V ÷ I
P = V × I
P = I² × R
P = V² ÷ R
Ohm's Law is a fundamental principle in electrical engineering that describes the relationship between voltage, current, and resistance in an electrical circuit. Our calculator makes it easy to find any unknown value when you know the other two.
This tool is essential for electronics students, electrical engineers, technicians, and hobbyists working with circuits. It can calculate voltage (V), current (I), resistance (R), and power (P) using the standard Ohm's Law formulas.
The calculator also includes power calculations, making it a comprehensive tool for electrical circuit analysis and design.
Input any two known values from voltage, current, resistance, or power. Leave the unknown fields empty.
Press the "Calculate" button to compute all unknown values using Ohm's Law formulas.
The calculator will display all four values (V, I, R, P) with the formulas used for calculations.
Use "Clear All" to reset all fields and perform new calculations with different values.
Given: Voltage = 12V, Resistance = 4Ω
I = V ÷ R = 12V ÷ 4Ω = 3A
P = V × I = 12V × 3A = 36W
Given: Voltage = 24V, Current = 2A
R = V ÷ I = 24V ÷ 2A = 12Ω
P = V × I = 24V × 2A = 48W
Given: Current = 0.5A, Resistance = 100Ω
V = I × R = 0.5A × 100Ω = 50V
P = I² × R = 0.5² × 100 = 25W
Given: Voltage = 9V, Current = 1.5A
P = V × I = 9V × 1.5A = 13.5W
R = V ÷ I = 9V ÷ 1.5A = 6Ω