kW to kVA Calculator - Power Factor Converter

Agarapu Ramesh — Editor and content reviewer
Editorially reviewed Reviewed by Agarapu Ramesh, science educator (chemistry). LinkedIn
Last reviewed: May 2026 | Standard electrical engineering formulas

kW is the useful power. kVA is what the supply equipment has to carry. If power factor is below 1, kVA will be higher than kW. That gap is why motor-heavy panels need bigger transformers than the kW number suggests.

Formula at a glance

  • kVA = kW / PF
  • PF = kW / kVA
  • VA = kVA x 1000

Field note: If you use PF 1 for everything, the answer will look tidy and the equipment may be too small. That is an expensive kind of tidy.

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kW to kVA Calculator

Convert real power to apparent power

kW
Result
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Formula

kVAS = P ÷ PF

Where:
S = Apparent Power (kVA)
P = Real Power (kW)
PF = Power Factor

Quick Reference (PF=0.8)

kW kVA
10 kW 12.5 kVA
25 kW 31.25 kVA
50 kW 62.5 kVA
100 kW 125 kVA

Related Calculators

kVA to kW Power Factor kVA to Amps

How to use the kW to kVA Calculator

Use this as a fast electrical check, then compare the result with the nameplate, measured voltage and power factor. The formula is clean. Real panels, motors and UPS loads usually have one extra wrinkle.

Worked example

Example: 12 kW at PF 0.8 needs 15 kVA. At PF 0.95 it needs 12.63 kVA.

Practical checks before you trust the number

  • Use realistic PF for motor and compressor loads.
  • Generators and UPS units usually have both kVA and kW ratings.
  • Leave margin for future loads and startup current.

Common mistake

If you use PF 1 for everything, the answer will look tidy and the equipment may be too small. That is an expensive kind of tidy.

Sources and references

Related calculators

Frequently Asked Questions

Divide kW by power factor. For example, 10 kW at PF 0.8 is 12.5 kVA.

Yes. It is useful for generator sizing because generators are commonly rated in kVA while loads are often listed in kW.

Yes. Without power factor you can only assume PF 1.0, which is accurate only for mostly resistive loads.

No. kVA = kW / PF still applies. Phase is needed when you convert kVA into amps.