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Free calculator

Use this calculator to

  • Convert UPS and inverter ratings between kVA and VA when comparing datasheets
  • Match a small load quoted in VA against a supply or UPS rated in kVA
  • Move between units quickly when adding up IT loads for a comms room

kVA to VA Calculator

Convert kilovolt-amps (kVA) to volt-amps (VA). Simple ×1000 conversion.

kVA
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Result
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Formulas

  • VA = kVA × 1000

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VA→kVA

VA to kVA

Convert volt-amps to kilovolt-amps

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kVA→A

kVA to Amps

Convert apparent power (kVA) to current (A)

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kVA→kW

kVA to kW

Convert apparent power (kVA) to real power (kW)

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Common scenarios

Select one to run it in the calculator above.

For business

Why this matters for businesses

UPS systems, isolation transformers, and IT load schedules are typically specified in VA, while the building's incoming supply and the LV switchroom are quoted in kVA. The conversion is trivial in isolation, but server rooms and edge-compute spaces are where small unit errors compound: a 30 kVA UPS feeding a 28,000 VA rack list looks comfortable until someone adds a second feed and the headroom disappears. Then the runtime number on the spec sheet is fiction.

Transformer sizing has the same pattern. A 1,000 kVA distribution transformer feeding a manufacturing site with a 600 kVA peak diversified load has roughly 40 percent headroom on paper, but power factor and harmonic distortion eat into that figure. For sites planning a new production line, a PV-plus-battery install, or an EV charger bank, knowing the actual VA picture rather than just the headline kVA is what makes the difference between a project that delivers and a project that needs the connection rebuilt halfway through.

Purely Energy works with clients where capacity planning and procurement decisions land in the same conversation. A new I&C tenant fit-out, a data hall extension, or a retrofit of resilient infrastructure all need the VA and kVA numbers right before the supply contract gets renegotiated. The free conversion tool sits at the start of that planning chain, and the half-hourly data and contract review sit at the end of it.

Common questions

How many VA are in a kVA?

Exactly 1,000. The k prefix is the standard SI kilo, so 1 kVA = 1,000 VA, 5 kVA = 5,000 VA and 0.65 kVA = 650 VA. The conversion carries no power factor or efficiency assumptions; it is the same quantity, apparent power, expressed at a different scale. Small devices tend to be labelled in VA and building-level supplies in kVA, which is why the conversion comes up so often.

What is the difference between VA and watts?

VA measures apparent power, the product of the voltage and current the supply must deliver. Watts measure real power, the part converted into useful work or heat. They are related by power factor: W = VA x PF. For a purely resistive load they match, but for IT equipment, motors and anything with a switched-mode power supply the watt figure is lower than the VA figure.

Why are UPS systems rated in VA or kVA?

Because a UPS is limited by the current its inverter and transformer can carry, which tracks apparent power, not just the real power of the load. Most UPS datasheets quote both a VA rating and a W rating, where the W figure reflects the design power factor. When sizing, your load must sit under both limits, whichever it reaches first.

Can I put 1,000 W of equipment on a 1,000 VA UPS?

Usually not. The watt capacity of a UPS is its VA rating multiplied by its rated output power factor, so a 1,000 VA unit rated at 0.9 supports at most 900 W. Check the W rating on the datasheet rather than assuming the VA figure, and leave headroom for inrush when equipment starts. If your load is quoted in amps, convert it via the kVA to amps calculator first.

Related calculators

The conversions that procurement and engineering use alongside this one.

kVA to VA Calculator | Free UK Tool | Purely Energy