Ohm’s Law Calculator

Calculate Voltage, Current, or Resistance using the fundamental relationship: V = I × R

How to use

Enter any two values to calculate the third:

• Voltage (V) - Potential difference
• Current (I) - Flow of charge
• Resistance (R) - Opposition to current

Examples

Example 1: Calculate Resistance

Given: 5V Voltage, 20mA Current Result: R = 5V / 0.02A = 250Ω

Example 2: Calculate Voltage

Given: 220Ω Resistor, 10mA Current Result: V = 220Ω × 0.01A = 2.2V

FAQ

Q: What units should I use? A: Use volts (V) for Voltage, amperes (A) for Current, and ohms (Ω) for Resistance.

Q: Does this work for AC circuits? A: This calculator is for DC circuits. AC circuits require additional considerations.