Easily convert kW to kVA with our free online calculator. Learn the kW to kVA formula, understand the role of Power Factor, and view our quick reference conversion table.
How to Convert Kilowatts (kW) to kVA
To convert Kilowatts (kW) to Kilovolt-Amps (kVA), you must divide the real power (kW) by the power factor (PF) of the electrical system. This conversion is necessary because many power sources, like generators, are rated in kVA, while the devices they power are usually rated in kW.
The Formula
The relationship between real power and apparent power is determined by the Power Factor:
kVA = Kilowatts (kW) ÷ Power Factor (PF)
If you do not know the exact power factor of your equipment, a standard Power Factor of 0.8 is typically used for general engineering estimates.
kW to kVA Conversion Table
Quick reference guide for common kW values converted to kVA using a standard 0.8 Power Factor:
| Real Power (kW) | Apparent Power (kVA) @ 0.8 PF |
|---|---|
| 1 kW | 1.25 kVA |
| 5 kW | 6.25 kVA |
| 10 kW | 12.5 kVA |
| 20 kW | 25.0 kVA |
| 50 kW | 62.5 kVA |
| 100 kW | 125.0 kVA |
Contextual Information
kW (Real Power) vs. kVA (Apparent Power)
In electrical systems, kW is “active power”—it is the energy that actually turns the motor, heats the water, or lights the room. kVA is “apparent power”—it is the total amount of energy being delivered through the wires. The difference is caused by the inefficiency of magnetic fields in devices like motors and transformers.
The Role of Power Factor (PF)
The Power Factor is a ratio between 0 and 1.
- A PF of 1.0 (Unity) occurs in purely resistive loads like heaters. In this case, kW = kVA.
- A PF of 0.8 is typical for most industrial and commercial buildings.
Why use this converter?
Calculating the kVA requirement is critical when purchasing a generator or installing a transformer. If your machinery draws 80 kW at a 0.8 power factor, you actually need a 100 kVA power source. If you bought an 80 kVA source, it would likely overheat or fail because it cannot handle the reactive power load.