When to use this calculator
The product of RMS voltage and current represents apparent power; multiplying by power factor gives real power.
Explore the ac power & reactance calculators for other questions in this topic. For a related calculation, use the Capacitive Reactance Calculator: Find capacitor reactance magnitude at a given sinusoidal frequency.
PUTTING IT INTO PRACTICE
AC Apparent Power: a worked example
The values below are an illustrative example, not a recommendation. Replace them with measurements or assumptions that match your question.
| Input | Example value |
|---|---|
| RMS voltage (V) | 230 |
| RMS current (A) | 10 |
| Result | 2,300 VA |
- Check the input labels and enter the example values above.
- Apply the relationship: Apparent power = RMS voltage × RMS current.
- The result is 2,300 VA, rounded for display.
How to interpret your result
For single-phase AC. Apparent power in VA differs from real power in watts.
Use RMS values in the AC power relationships. Apparent power is measured in VA and real power in watts. Pure-sine conversions and balanced three-phase equations only apply under their stated assumptions.
Frequently asked questions
Why can volt-amps differ from watts?
Apparent power is the RMS voltage-current product, while real power also reflects power factor. They are numerically equal only at a power factor of one.
When is the ac apparent power calculator useful?
The product of RMS voltage and current represents apparent power; multiplying by power factor gives real power.
How do I use the ac apparent power calculator?
Enter rms voltage (v), rms current (a). The result updates automatically. Use the units shown beside each input; the example values illustrate the method.
Which formula does this calculator use?
Apparent power = RMS voltage × RMS current.
What should I check before using the result?
For single-phase AC. Apparent power in VA differs from real power in watts.
How are results rounded?
Scalar numbers display up to six decimal places, with scientific notation for very large or small values. Text, fraction, date and schedule outputs use the format described on the tool. Intermediate calculations use JavaScript floating-point arithmetic. Keep sensible precision for your measurements.
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