Ohm's Law Calculator

Apply Ohm's Law to find voltage, current, or resistance in a circuit. Enter any two values to solve for the third.

V
A

Resistance

24.00 Ω

Power6.000 W

Resistance vs Voltage

How Ohm's Law Works

Ohm's Law links voltage, current, and resistance.

Formula

V = I x R

Where:

  • V = Voltage in volts
  • I = Current in amperes
  • R = Resistance in ohms
  • Rearranging gives R = V / I and I = V / R. Power is P = V x I.

    Example Calculation

    A 12 V battery drives 0.5 A through a resistor.

    1. 01Resistance R = V / I = 12 / 0.5 = 24 ohms
    2. 02Power P = V x I = 12 x 0.5 = 6 W

    Frequently Asked Questions

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    Ohm's Law Guide

    A complete guide to Ohm's Law. Learn the relationship between voltage, current, and resistance, with practical examples, the power triangle, and circuit analysis tips.

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