Electrical Power Calculator

Calculate electrical power using P = V × I, P = I²R, or P = V²/R. Enter any two values to find power and the missing variable.

Enter any two values to calculate power.

Voltage (V)

Current (A)

Resistance (Ω)

Enter any two values.

Power Formulas

P = V × I
P = V² / R
P = I² × R

Example: 120 V × 2 A = 240 W

Last updated: 2026-08-08