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
V12 VR6 ΩI = 2 AV = I × R

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