What this calculator actually does
Electrical power depends on current and voltage. For AC systems, real power can also depend on power factor; balanced three-phase power uses √3 when line-to-line voltage is entered.
How to use this calculator
Choose DC, single-phase AC or balanced three-phase AC.
Enter current, voltage and—for AC—the applicable power factor. Three-phase mode uses line-to-line voltage.
Review watts and kilowatts, then verify the assumptions against the equipment data.
Where people use it
- •Equipment power sanity checks
- •Converting measured current to approximate real power
- •Electrical training and formula verification
Example: 10 A at 230 V, PF 1
For DC or a unity-power-factor single-phase load, 10 × 230 = 2,300 W, or 2.3 kW.
Assumptions and limits
- •This is a power calculation, not a breaker, conductor or code-compliance recommendation.
- •Unbalanced three-phase systems, harmonics, efficiency and nonlinear loads can require more detailed analysis.
Frequently asked questions
How many watts is 1 amp?+
There is no fixed answer without voltage. In DC, watts equal amps multiplied by volts.
Why is power factor included for AC?+
Power factor relates real power to apparent power; a lower power factor means the same volts and amps can correspond to less real power.
What voltage does three-phase mode use?+
This calculator uses line-to-line voltage in the balanced three-phase formula.
Semantic next steps
Continue the calculation
These links move to a different input, formula or project stage rather than a keyword variation of this page.
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