FREE ONLINE TOOL

Free Electrical Power
Calculator

Solve voltage, current, resistance and power, check resistor loading, analyze a loaded voltage divider, or design an LED series resistor with preferred-value recommendations — entirely in-browser.

About Free Electrical Power Calculator

Advanced free Ohm's law calculator for V, I, R and P, resistor power-rating checks, loaded voltage dividers, LED resistor design, unit conversion, circuit diagrams and local-only processing.

Workspace options

  • Voltage V
  • Current I
  • Resistance R
  • Power P
  • Consistency tolerance (%)

Available actions

  • ☼ / ◐
  • V · I · R · P solver
  • Resistor rating
  • Loaded divider
  • LED resistor
  • 5 V + 10 Ω