Quick answer
Apparent power in VA = real power in watts ÷ power factor. 8 kW at a power factor of 0.8 is 10,000 VA, or 10 kVA.
Enter real power and the power factor. The calculator returns apparent power in VA and kVA.
Related tools: Ah ⇄ Wh Converter: Convert between amp-hours, milliamp-hours and watt-hours.
How to use the kW to VA Converter
- Enter real power (kW) (above 0).
- Enter power factor (between 0 and 1).
- Press Calculate to see the result, and use Reset to start again.
| Input | What to enter | Allowed values |
|---|---|---|
| Real power | A number, in kW | > 0 |
| Power factor | A number | > 0, ≤ 1 |
Formula and method
Formula
VA = kW × 1000 ÷ pf
IEEE-754 double precision; shown to the decimals indicated.
For power in kVA divide by 1000; kVA to kW multiply by pf.
Worked examples
These examples are verified: each one is an automated test case that the live calculator must reproduce exactly.
Example 1
Inputs: Real power = 8; Power factor = 0.8.
| Result | Value |
|---|---|
| Apparent power | 10,000 VA |
| In kVA | 10 |
Example 2
Inputs: Real power = 50; Power factor = 0.95.
| Result | Value |
|---|---|
| Apparent power | 52,631.58 VA |
| In kVA | 52.6316 |
Example 3
Inputs: Real power = 3.5; Power factor = 1.
| Result | Value |
|---|---|
| Apparent power | 3,500 VA |
| In kVA | 3.5 |
The first line is the headline result (apparent power). Below it the kW to VA Converter lists in kVA, which describe the same case from other angles. IEEE-754 double precision; shown to the decimals indicated.
Why VA exceeds W
Inductive loads such as motors draw current that does no useful work, so apparent power (VA) exceeds real power (W). The ratio is the power factor. At 0.8, every 8 kW needs a 10 kVA supply.
Sizing equipment
Generators, transformers and UPS units are rated in kVA, so convert load watts to VA, not the reverse. The power factor must be between 0 and 1; use 1 for resistive loads such as heaters.
How the result changes with real power
Holding every other input at the first worked example, this table changes only real power. It shows how sensitive the answer is to that one value; each row was produced by running this calculator.
| Real power | Apparent power | In kVA |
|---|---|---|
| 4 | 5,000 VA | 5 |
| 8 | 10,000 VA | 10 |
| 16 | 20,000 VA | 20 |
| 32 | 40,000 VA | 40 |
What happens with invalid input
These messages are produced by the calculator itself, so you know what to fix.
- Real power: entering "0" shows "Real power must be greater than 0." beside that field and no result.
- Power factor: entering "0" shows "Power factor must be greater than 0." beside that field and no result.
Choosing between the kW to VA Converter and similar calculators
Each row shows what a related calculator on this site asks for and what it returns, so you can pick the one that matches your question.
| Calculator | You enter | It returns |
|---|---|---|
| [Ah ⇄ Wh Converter](/converters/ah-to-wh-calculator/) | convert, value and voltage | Energy |
| [Ohm's Law Calculator](/engineering/ohm-s-law-calculator/) | Current | |
| [Parallel Resistor Calculator](/engineering/parallel-resistor-calculator/) | resistances | Parallel resistance |
| [Watt-Hours Calculator](/engineering/watt-hours/) | use | Energy |
| [LC Resonant Frequency Calculator](/engineering/resonant-frequency-lc/) | inductance and capacitance | Resonant frequency |
Background: unit conversion
Many customary units are defined exactly in terms of metric ones: since the 1959 International Yard and Pound Agreement an inch is exactly 2.54 cm and a pound is exactly 0.45359237 kg (NIST SP 811 lists these). So most length and mass conversions are exact apart from the rounding of the displayed result.
To convert, multiply the value by the source unit's factor to reach the base unit, then divide by the target unit's factor; the unit table on this page lists every factor used. Temperature and fuel economy are the exceptions, because they are not simple multiples.
Assumptions and limitations
- Power factor between 0 and 1
If a required value is empty, not a number, or outside its allowed range, the form marks that field with a message and shows no result instead of a misleading number. The automated checks deliberately try invalid entries for real power and power factor to confirm this.
Frequently asked questions
What is a typical power factor?
Motors are often 0.7 to 0.9; resistive loads are 1.
Is VA the same as W?
Only at a power factor of 1.
How many amps is 10 kVA?
At 240 V single phase, about 41.7 A.
What does the kW to VA Converter calculate?
Apparent power in VA from real power and power factor. It returns Apparent power and In kVA.
What formula does the kW to VA Converter use?
VA = kW × 1000 ÷ pf. For power in kVA divide by 1000; kVA to kW multiply by pf.
What do I need to enter in the kW to VA Converter?
You enter Real power (kW) and Power factor.
How is the result rounded or limited?
IEEE-754 double precision; shown to the decimals indicated. Power factor between 0 and 1.
What is an example of a kW to VA result?
With real power 8 and power factor 0.8, the apparent power is 10,000 VA.
Related calculators
- Ah ⇄ Wh Converter — Convert between amp-hours, milliamp-hours and watt-hours.
- Power Factor Calculator — Power factor, phase angle and reactive power from real and apparent power.
Sources
- OpenStax, Prealgebra 2e (Rice University): fractions, decimals, percents, ratios and rounding
Content last reviewed 2026-11-04. Formulas and worked examples are checked by automated tests against independently computed values.