Ohm's Law

Solve V = I × R — enter any two of voltage, current, and resistance to find the third

V = I × R → 12 V = 2 A × 6 Ω

Voltage (V) (V)

12 V

Current (I) (A)

2 A

Resistance (R) (Ω)

6 Ω

Power (P = V × I)

24 W

About this calculator

The Ohm's Law Calculator helps you find voltage, current, or resistance when you know the other two values. Based on the fundamental formula V = I × R, this tool is essential for electronics, circuit design, and physics coursework. Enter any two values to instantly calculate the missing third.

Common examples

V = 5 A × 10 Ω = 50 V
I = 120 V ÷ 60 Ω = 2 A
R = 9 V ÷ 0.3 A = 30 Ω
V = 0.5 A × 220 Ω = 110 V
I = 12 V ÷ 4 Ω = 3 A