ruchira
// ENGINEERING TOOL

Ohm's law, power & divider calculator

Solve voltage, current, resistance and power from any two values, combine series and parallel resistors and design voltage dividers and LED resistors.

  • Free
  • No sign-up
  • Private: runs in your browser
// HOW IT WORKS

4 steps, no sign-up.

Built and maintained by Ruchira Sachinthana. Spotted a bug or want a feature? Tell me.

  1. 01Pick the calculator: Ohm's law, series/parallel, voltage divider or LED resistor.
  2. 02Enter the values you know, with any unit prefix.
  3. 03Read the results, shown with SI prefixes.
  4. 04Check the power rating before choosing parts.
// FAQ

Ohm's law calculator: questions, answered.

Something else? Ask on WhatsApp.

Yes. 4k7, 4.7k, 4700 and 4.7e3 all mean 4.7 kΩ, and m, µ (or u), k and M prefixes work everywhere.

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// CUSTOM TOOLS

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