About the kVA to kW Calculator
This calculator converts kVA to kW. kVA is a thousand volt-amperes, the apparent power rating of transformers, generators and UPS units, and kW is a thousand watts, the usual way to rate motors, heaters, air conditioners and generators. It multiplies the apparent power by the power factor and shows the reactive part as well. Enter your figures and the answer appears at once, together with a few related values, and you can copy the result with one tap. The sums are done in your browser and nothing is sent anywhere.
Updated October 2026
How to use the kVA to kW Calculator
- 1Enter the value in kVA.
- 2Fill in the other boxes that the kVA to kW calculation needs, such as time, voltage or power factor.
- 3Read the answer in the large result box.
- 4Check the extra rows for related values.
- 5Press Copy result to keep it.
When you need kVA to kW
Generators, transformers and UPS units are rated in kVA, but equipment you plug in uses kilowatts. The link between them is the power factor. A 10 kVA unit can supply 8 kW at a power factor of 0.8, or the full 10 kW if the load is purely resistive.
Use this when choosing a generator for a workshop: add up the kilowatts of the machines, divide by the power factor to get the kVA needed, or use this tool the other way round to find how much real power an existing unit offers.
How the kVA to kW sum works
kW = kVA × power factor. A 10 kVA generator feeding a load with a power factor of 0.8 delivers 10 × 0.8 = 8 kW, and the rest, 6 kVAR, is reactive power.
The displayed answer is rounded to six significant figures, but the sum itself is not rounded, so converting kVA to kW and back again gives you the number you started with.
- Typical generator rating: 0.8
- Resistive loads: 1
- Motors: 0.7 to 0.9
Mistakes to avoid when converting kVA to kW
Never assume that kVA equals kW. Using the two as the same overstates the usable power and leads to overloaded equipment. Use the power factor of the actual load, or 0.8 as a typical value for mixed industrial loads.
On phone and computer
On a phone, type in the boxes one after another and read the kW result underneath; the Copy button puts it on the clipboard for a message or a note. On a computer the inputs sit on the left and the answer on the right, so you can change one figure and watch the kW value move. The kVA to kW page works the same on both. The answer depends on the power factor, so check the factor with Power Factor Calculator. If you start from real power, kW to kVA Calculator reverses the step, and Amps to kVA Calculator gets you there from a current reading.
Features
- kVA to kW in one step
- Related values shown with the answer
- Clear messages for impossible inputs
- Copy the result with one tap
- Private: nothing is uploaded
- Works on phone and computer
Frequently asked questions
How do I convert kVA to kW?
kW = kVA × power factor. A 10 kVA generator feeding a load with a power factor of 0.8 delivers 10 × 0.8 = 8 kW, and the rest, 6 kVAR, is reactive power.
What is the formula for kVA to kW?
kW = kVA × power factor. The calculator applies it exactly and rounds only the displayed answer.
What is the difference between kVA and kW?
kVA is a thousand volt-amperes, the apparent power rating of transformers, generators and UPS units. kW is a thousand watts, the usual way to rate motors, heaters, air conditioners and generators. They measure different things, which is why converting from kVA to kW needs more than a simple multiplication in some cases.
What is the power factor of a generator?
Generators are often rated at 0.8. That means a 100 kVA unit supplies 80 kW. The rating plate states the exact value.
What is reactive power?
The part of the apparent power that moves back and forth without doing work. It is shown as kVAR and equals the square root of kVA squared minus kW squared.
Is this kVA to kW calculator free and private?
Yes. It is free, needs no account, and runs in your browser, so the figures you type are not uploaded or stored. It is meant for planning and learning; for wiring or safety work, check the result against your equipment's rating plate and local rules.