Back to directory
Ohm's law

Relate voltage, current, resistance, and power in one glance.

Pick any two parameters and we'll compute the rest using the standard Ohm's law relationships for quick schematic checks and sanity validation.

12.00 V

Voltage

0.500 A

Current

6.00 W

Power

Known values

V
A

Solved parameters

Voltage

12.000 V

Current

0.500 A

Resistance

24.00 Ω

Power

6.00 W

Power envelope

6.00 W

Use this to size resistors and FET thermal limits.

Current density tips

Keep <35 A/mm²

Beyond this, electromigration risk rises fast on fine features.

Design notes

  • Double-check units—mixing milliamps and amps skews results 1000x.
  • Always include component tolerance when you back-solve for a missing value.
  • Use the power result as a baseline; derate resistors by at least 50% for reliability.
Ohm's Law Calculator - Voltage, Current, Resistance | Free