OneTool

Electrical Power Calculator

Power-focused solver with convenient unit prefixes.

Solve focus
Power unit

Fill any two of V, I, R, P (or pick a solve focus to clear that field). Uses Ohm's law and power identities.

Voltage

12 V

Current

2 A

Resistance

6 Ω

Power

24 W

What is this tool?

Electrical power ties voltage, current, and resistance together through P = V·I, P = I²R, and P = V²/R. This calculator emphasizes power results with mW / W / kW display options.

How to use it

  1. Enter at least two known values among V, I, R, and P.
  2. Choose the power unit prefix that matches your scale.
  3. Confirm continuous and peak ratings on real components.