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kVA to kW calculator, with power factor

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10 kVA, power factor 0.8 works out at 8.00 kW: 10 kVA × 0.8 = 8.00 kW.

What to convert

Between 0.01 and 1,000,000

Power factor

Leave empty for 1 (heaters, kettles) or 0.8 for kVA (generators).

Power factor is at most 1 (and at least 0.1)

See result ↓

Your result

Result

8.00 kW

10 kVA × 0.8 = 8.00 kW

You typed
10 kVA, power factor 0.8
Power factor used
0.8

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How we calculated this

  • Multiply the volts by the power factor. Amps are the watts divided by that.
  • On three phase, the volts are also multiplied by the square root of three before dividing.
  • kW is kVA times power factor. An empty voltage means the standard at the meter.

Full method, tables and sources: Watts to amps calculator

  1. Check the inputs

    10 kVA, power factor 0.8

  2. Use the formula

    10 kVA × 0.8 = 8.00 kW

This version starts with a 10 kVA generator at a power factor of 0.8. Type your kVA and the power factor on its plate.

kVA to kW: what to know

Official source

  • Large generator sets are rated at a power factor of 0.8 (ISO 8528). A Caterpillar set rated 770 kVA is 616 kW.
  • A heater has a power factor of 1. An induction motor is 0.85 at full load and 0.17 with no load (Schneider Electric). So kVA equals kW only for heaters and kettles.
  • Of 122 LED lamps tested in Australia, 18 had a power factor under 0.5 (E3, 2017).
kVA to kW at power factor 0.8, 0.85 and 1
kVAPower factor 0.8Power factor 0.85Power factor 1
10.80 kW0.85 kW1.00 kW
54.00 kW4.25 kW5.00 kW
108.00 kW8.50 kW10.00 kW
2016.00 kW17.00 kW20.00 kW
5040.00 kW42.50 kW50.00 kW
10080.00 kW85.00 kW100.00 kW
  • The three columns are three kinds of load: 0.8 is the power factor large generator sets are rated at, 0.85 is an induction motor at full load, and 1 is a heater or kettle, where kVA and kW are the same figure.
  • Going the other way, the kW to kVA mode divides by the power factor: 10 kW ÷ 0.8 = 12.50 kVA.
  • The kVA also sets the amps, whatever the power factor: 10 kVA is 43.48 A at 230 V single phase and 14.43 A per phase at 400 V three phase.

Every cell is the calculator on this page, run for that row. 0.8 is the power factor large generator sets are rated at, which is our choice of default (Estimate). 0.85 and 1 are Schneider Electric's practical values (Official source). An estimate, not electrical advice. Ask a licensed electrician.

Power factor at part load and for lighting

A motor's power factor falls with its load

An induction motor's power factor is 0.8 at 75% load, 0.73 at 50% load and 0.55 at 25% load. An uncompensated fluorescent light is 0.5, and a compensated one 0.93.

Source: Schneider Electric Electrical Installation Guide, Fig. L7, practical values of power factor (read via the Wayback Machine) (Official source). Checked 30 September 2026.

So 10 kVA is 8.50 kW of motor at full load (the middle column of the table) and 5.50 kW at 25% load. For the two lights, 10 kVA is 5.00 kW and 9.30 kW.

For power points, power factor and 230 or 240 V, see the main watts to amps calculator.