Example
10 A at 230 V single phase
The load has a 0.9 power factor.
Apparent power = 230 × 10 = 2,300 VA Real power = 230 × 10 × 0.9 = 2,070 W
Result: 2,070 W.
Power calculator
Amps to Watts Calculator
Convert current to real power using the relationship for your electrical system. AC results keep power factor and apparent power visible.
Real power2,070 W
Calculation breakdown
| System | Single-phase AC |
|---|---|
| Apparent power | 2,300 VA |
| Power factor | 0.9 |
Real power (W) = voltage (V) × current (A) × PF = 230 × 10 × 0.9 = 2,070 W
Method
How the number is reached
DC real power is voltage multiplied by current. Single-phase AC additionally multiplies by power factor; balanced three-phase also multiplies by √3 when using line-to-line voltage.
Apparent power in VA is shown because current-carrying equipment responds to volts and amps even when real watts are lower due to power factor.
DC: P = V × I Single phase: P = V × I × PF Three phase: P = √3 × VLL × IL × PF
Symbols
- PF
- Power factor
- VLL
- Line-to-line voltage
Worked examples
The same maths, applied
Limits of the model
What it assumes, and where it stops
Assumptions
Three-phase loads are balanced.
Not covered
Does not model harmonics, unbalance, waveform distortion or time-varying current.
Sources
Where these figures come from
- Electrical Installation Guide (IEC-based)Schneider ElectricReference for single-phase and three-phase power relationships and power factor.
- IEC 60050 — International Electrotechnical Vocabulary (Electropedia)International Electrotechnical CommissionStandard terminology for electrical quantities, including apparent power and power factor.
- SI UnitsNIST Office of Weights and MeasuresDefinitions of the volt, ampere, watt and joule used for the unit conventions on this site.
Next steps
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Last meaningful update: 2026-08-19. This date changes only when the model, the sources or the guidance change.