kVA ↔ kW Power Factor Converter

Convert between apparent power (kVA) and real power (kW) to size generators, UPS units, or transformers. Choose the conversion direction, enter the load’s power factor, and optionally add design headroom for motor inrush or future expansion.

Magnitude of the quantity (enter kVA if using default forward mode).
Overall power factor of the load (enter 80 for 0.80 pf).
Optional. Default 1 (convert apparent kVA to real kW).
Optional. Default 0% — add spare capacity for motor inrush or future load.

Results assume a steady-state power factor. Verify with nameplate data and harmonic studies for critical infrastructure.

Examples

  • Generator rated 25 kVA at 0.80 pf, default headroom ⇒ Input 25.00 kVA at pf 80.00% ⇒ real power 20.00 kW, reactive 15.00 kVAr (angle 36.87°). No extra headroom applied.
  • Load needs 12 kW at 0.92 pf, 10% spare capacity ⇒ Input 12.00 kW at pf 92.00% ⇒ required apparent power 13.04 kVA, reactive 5.12 kVAr (angle 23.07°). Headroom applied: 10.00% ⇒ order 14.35 kVA.

FAQ

How do I handle leading power factor?

Enter the absolute value of the power factor. Leading or lagging simply affects whether you add capacitive or inductive support; the magnitude determines the conversion.

Can this calculate three-phase current?

Not directly. After converting to kW or kVA, use the line voltage and √3 × V × I relationship to compute current.

What headroom should I use for motor loads?

Industrial practice typically adds 15–25% to cover locked-rotor inrush. Adjust the headroom field based on your motor type and utility limits.

Additional Information

  • Apparent power (kVA) combines both real (kW) and reactive (kVAr) components; multiplying kVA by power factor yields kW.
  • Reactive power comes from the sine component of the power triangle (kVAr = kVA × √(1 − pf²)). Use it to size capacitor banks for correction.
  • Headroom lets you reserve additional kW or kVA to accommodate motor starts, harmonics, or future loads.

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