kVA to kW Calculator
This kVA to kW calculator converts apparent power in kVA into real power in kW using the power factor. Enter the kVA and the power factor and the kVA to kW calculator returns the kW. The math behind kVA into kW is the same for single phase and three phase, so one kVA to kW formula covers both.
Results
The kVA to kW Calculator is part of our AC & Three Phase collection. Browse more ac & three phase to size, convert, and check your work alongside this tool.
What kVA into kW conversion means
kVA is apparent power, the total power an AC system carries, while kW is real power, the part that does useful work. kVA into kW conversion multiplies the apparent power by the power factor, which is the fraction of the current that lines up with the voltage. This kVA to kW calculator does that step for you, so the conversion of kVA into kW takes one entry instead of a hand calculation.
The kVA to kW formula
The kVA to kW formula multiplies apparent power by the power factor:
PF is the power factor, a number between 0 and 1. Because the power factor already carries the phase relationship, the same kVA to kilowatt formula works for single phase and three phase supplies, so there is no separate three phase version. That is why this kVA to kw calculation formula matches both a small single phase panel and a large three phase feeder.
kVA to kW conversion example
A 100 kVA transformer running at a power factor of 0.8. The kVA to kW calculator applies the kVA to kw conversion:
So 100 kVA delivers 80 kW of real power. Change the power factor and the kVA to kW calculator updates the conversion of kva into kw right away.
How to use the kVA to kW calculator
Enter the apparent power in kVA and the power factor as a decimal between 0 and 1, then the kVA to kW calculator returns the real power in kW. A power factor of 0.8 is a common default for motors, while resistive loads sit near 1.0. To convert 1kVA into kW at a power factor of 0.8, you get 0.8 kW, and every other value scales the same way.
Reading the kVA to kilowatt calculator result
The kW value is the real power that turns motors and heats elements; the difference between kVA and kW is reactive power, which the power factor sets. A low power factor means more of the kVA is wasted, so the kW falls well below the kVA. The kVA to kilowatt calculator shows this gap: at a power factor of 1.0 the kW equals the kVA, and as the power factor drops the kW shrinks. Use it to size generators and transformers by the real load they must carry.
When to convert kVA to kW
- Sizing a generator, where you convert kva to kw to match the real load
- Rating a transformer with the kVA to kW calculator
- Checking a nameplate that lists kVA but not kW
- Comparing apparent and real power on a bill
Common kVA to kW conversion mistakes
- Assuming kVA equals kW. That only holds at a power factor of 1.0; otherwise the kva to kw conversion needs the real power factor.
- Looking for a separate 3 phase formula. The kva to kw formula is the same once you have the kVA.
- Entering power factor as a percent. Use a decimal, so 80 percent becomes 0.8 before you convert kva to kw.
Tips for accurate conversions
- Read the power factor from the nameplate rather than guessing when you can.
- Use 0.8 as a safe default for mixed motor loads.
- Size generators on the kW they must deliver, not the kVA alone.
The kVA to kW formula 3 phase and single phase
People expect a separate kva to kw formula 3 phase, but there is not one when you work from apparent power. Apparent power in kVA already sums the three phases, and the power factor already holds the angle between voltage and current, so kW = kVA × PF gives the real power for any AC system. The place a three phase term appears is one step earlier, when you build the kVA from line voltage and current, where a factor of the square root of three shows up. Once you have the kVA, the conversion of kva into kw is identical, which is why this one three phase power calculator pairs cleanly with the kVA step.
Why kVA to kilowatt conversion needs power factor
The power factor is the whole reason kVA and kW differ. In a purely resistive load the current and voltage rise and fall together, the power factor is 1.0, and the kVA equals the kW. Add motors, transformers, or fluorescent gear and the current lags the voltage, the power factor drops, and part of the apparent power becomes reactive power that does no work. That is why every kVA to kilowatt conversion asks for the power factor: without it you cannot tell how much of the kVA turns into useful kW, and a guess can oversize or undersize the equipment.
kVA into kW conversion chart
Common kVA into kW conversions at two power factors, from the kVA to kW calculator:
| kVA | kW at PF 0.8 | kW at PF 1.0 |
|---|---|---|
| 1 kVA | 0.8 kW | 1 kW |
| 10 kVA | 8 kW | 10 kW |
| 100 kVA | 80 kW | 100 kW |
| 500 kVA | 400 kW | 500 kW |
kVA to kW Calculator FAQ
What is the kVA to kW formula?
The kVA to kW formula is kW = kVA × PF. The kVA to kW calculator multiplies the apparent power by the power factor to give the real power in kW.
How do you convert 1kVA into kW?
Multiply by the power factor. To convert 1kVA into kW at a power factor of 0.8 you get 0.8 kW; at a power factor of 1.0 you get 1 kW.
Is the kVA to kW formula different for 3 phase?
No. Because the power factor carries the phase angle, the kva to kw formula 3 phase is the same as single phase: kW = kVA times the power factor.
Why is kW lower than kVA?
kVA is total apparent power and kW is only the working part. The power factor sets the ratio, so a power factor below 1.0 makes the kW smaller than the kVA.