Geometry & Science

Ohm's Law Calculator

Solve voltage, current, resistance and power from any two known electrical values.

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How to use this ohm's law calculator

Enter the requested values above and select Calculate. Change the inputs to compare scenarios.

Formula and method

V = I × R. Power P = V × I.

Example

With 12 V and 2 A, resistance is 6 Ω and power is 24 W.

What this calculator is useful for

Solve voltage, current, resistance and power from any two known electrical values.

Frequently asked questions

What does this calculator do?

Solve voltage, current, resistance and power from any two known electrical values.

What data or formula does it use?

Uses ideal DC Ohm’s law relationships. Real circuits can include reactive, nonlinear and temperature-dependent behavior.

Is it free?

Yes. ERICH Calculators is free to use and no account is required.

Source & assumptions

Reference and limitation

Uses ideal DC Ohm’s law relationships. Real circuits can include reactive, nonlinear and temperature-dependent behavior.

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Method, assumptions & corrections

See how formulas, sources and limitations are handled across ERICH Calculators.