kW to kVA Calculator

kW tells you the work a load does; kVA tells you how much current the supply has to carry to do it. For any inductive load the two numbers differ — and it is the kVA that decides the size of generators, transformers, UPS units and cables.

kW to kVA Calculator converts real power up to apparent power at your power factor, showing the reactive kilovolt-amps the load also pulls. The result is the rating number you size equipment on.

Everything runs in the browser; nothing is uploaded.

• Convert kW to kVA: At any power factor from 0.3 to 1.
• Reactive component: kVAr shown, so the power triangle is explicit.
• Load presets: 1.0 resistive, 0.9 electronics, 0.8 classic, 0.7 poor.
• Live formula: kVA = kW / pf, recomputed as you type.
• Export: Copy or download as text, CSV or JSON.
• Learning guide: Why the kVA you buy must exceed the kW you use.

1. Enter the real power in kW.
2. Select or enter the power factor — 0.8 for mixed loads.
3. Read the apparent power in kVA the source must provide.
4. Check the reactive kVAr to understand where the extra goes.
5. Export the conversion if needed.

Example 1 — Generator. 80 kW of site load at 0.8 pf needs a 100 kVA generator.

Example 2 — Transformer. 144 kW at 0.9 pf requires a 160 kVA transformer.

Example 3 — UPS. 45 kW of IT at 0.9 pf = 50 kVA UPS.

Example 4 — Motor-heavy. 120 kW at 0.7 pf demands about 171 kVA supply — pf correction would pull that down fast.

• Size equipment correctly: The kVA number you actually order from.
• Reactive clarity: See the kVAr you are paying to carry.
• Explained maths: The division shown live in the formula line.
• Export ready: Text, CSV and JSON for specs and quotes.
• Free and private: No uploads, no accounts, no logging.