Ohm's Law Calculator

About Ohm's Law Calculator

Solve voltage, current, or resistance and calculate circuit power.

How to Use

Solve voltage, current, or resistance and calculate circuit power. Enter the Solve for, Voltage, Current, and Resistance values and review the Voltage, Current, Resistance, and Power outputs after you calculate.

  1. Open the calculator : Use Ohm's Law Calculator from the Physics category.
  2. Check the inputs : Review the required values and any optional settings.
  3. Read the formula : Use the formula and notes below to understand how the result is produced.

Common Questions

What formula does the Ohm's Law Calculator use?

V = I x R. P = V x I.

What is Ohm's Law?

Ohm's Law is a fundamental rule in electronics stating that current (I) is equal to voltage (V) divided by resistance (R). The standard formula is mathematically expressed as V = I × R.

How do you calculate wattage using Ohm's Law?

While technically part of Joule's Law, power (Watts) is commonly calculated alongside Ohm's law. To find wattage, multiply the Voltage by the Current (Amps). The formula is P = V × I.

Inputs

  • Solve for
  • Voltage
  • Current
  • Resistance

Outputs

  • Voltage
  • Current
  • Resistance
  • Power

Formula

V = I x R. P = V x I.