Calculation Results


This page shows how to convert real power (kW) into apparent power (kVA). You need the power factor (PF) to do the conversion. PF is usually between 0 and 1.

Core formula

Convert kW to kVA

kVA = kW ÷ PF

PF must be > 0. If PF = 1 (purely resistive load), kVA equals kW. If PF < 1, kVA is larger than kW.

How to use

  1. Enter the real power in kW.
  2. Enter the power factor (PF). Use a measured PF when possible.
  3. Compute kVA = kW ÷ PF. Round as needed.

Examples

Example 1 — PF = 1.00 (resistive)

kW = 50, PF = 1.00 → kVA = 50 ÷ 1.00 = 50.00 kVA

Example 2 — Typical motor (PF = 0.85)

kW = 50, PF = 0.85 → kVA = 50 ÷ 0.85 ≈ 58.82 kVA

Example 3 — High power factor (PF = 0.95)

kW = 120, PF = 0.95 → kVA = 120 ÷ 0.95 ≈ 126.32 kVA

Quick reverse

To convert back: kW = kVA × PF.

Single-phase and three-phase note

The numerical relation kVA = kW ÷ PF is the same in single- and three-phase systems. What differs is how you compute kW or kVA from voltage and current. Once you have kW and PF, multiply or divide by PF as above.

Common mistakes

  • Using PF = 0 (invalid). PF must be positive and normally ≤ 1.
  • Using an assumed PF when the real load is highly non-linear. Use a meter to measure PF if accuracy matters.
  • Mixing units (W vs kW). Convert W to kW by dividing by 1000.
  • Rounding too early. Keep precision through the calculation and round at the end.

Practical tips

  • Motors and inductive loads often have PF around 0.75–0.9 unless corrected.
  • Improving PF lowers kVA for the same kW. That can reduce transformer or cable sizing and losses.
  • For billing and sizing, use the measured PF of the installation rather than a textbook value.

FAQ

What is kVA?

kVA is apparent power. It equals voltage times current (RMS) and shows the total capacity the system must carry.

What is kW?

kW is real (active) power. It is the power that actually does useful work or is converted to heat.

What is power factor (PF)?

PF is the ratio of real power to apparent power. For simple sinusoidal systems PF = cos(φ), where φ is the phase angle between voltage and current.

Can PF be greater than 1?

No for normal passive loads. PF > 1 indicates incorrect measurement or a nonstandard definition.

Why convert kW to kVA?

Equipment like transformers and generators are sized in kVA. To pick correct equipment you must know the apparent power requirement, not just kW.

What if the load is non-linear (harmonics)?

Non-linear loads change the true power factor (distortion). Use a power meter that reports true PF for accurate conversions.

How precise should PF be?

Use a measured PF where possible. For rough sizing, two decimal places is usually fine (for example 0.85 or 0.95).

How do I check my result?

Confirm units and check that kVA ≥ kW when 0 < PF ≤ 1. If your kVA is smaller than kW, re-check PF and units.