Ohm Power Calculator

Enter any two parameters below and click calculate to get the other two.

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Please fill in exactly two parameters. The calculator will compute the other two.
Calculated Result
Formula Diagram
Common Formulas
\(U = I \times R\)
\(P = U \times I\)
\(P = I^2 \times R\)
\(P = \frac{U^2}{R}\)

Ohm’s Law and Power Calculation

Ohm’s law describes the relationship between voltage, current, and resistance: U = I × R.

Electrical power measures energy conversion rate. Common formulas include P = U × I, P = I² × R, and P = U² / R.

With any two parameters known, the remaining two can be derived from the formula set, which is helpful for quick circuit estimation.

Keep units consistent: resistance in ohms, current in amperes, voltage in volts, and power in watts.

FAQ: Ohm Power Calculator

1. What is the basic formula of Ohm’s law?

U = I × R.

2. How do you calculate current from voltage and resistance?

I = U ÷ R.

3. How do you calculate power from current and resistance?

P = I² × R.

4. How do you calculate power from voltage and current?

P = U × I.

5. How do you calculate current from power and voltage?

I = P ÷ U.

6. How do you calculate resistance from power and current?

R = P ÷ I².

7. Why do I only need two inputs?

There are only two independent relationships, so two values uniquely determine the other two.

8. Are decimal results expected?

Yes, electrical calculations often produce decimals, and the tool keeps practical precision.

9. What happens if units are inconsistent?

Results will be off, for example mixing mA and A creates a 1000× error.

10. When should I use this calculator?

Use it for circuit design, power estimation, component selection, learning, and lab calculations.

Ohm Power Calculator

Provide any two parameters and automatically derive the other two for circuit analysis.

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