kW to kVA Calculator
Convert real power in kilowatts (kW) to apparent power in kilovolt-amps (kVA). Enter the real power and the power factor (greater than 0, up to 1), and press Calculate to get apparent power using S(kVA) = P(kW) / PF. Everything runs locally in your browser.
Enter the real power
Type the real power P in kilowatts (kW) — the working power drawn by the load. Negative values are rejected; 0 kW is valid and gives 0 kVA.
Enter the power factor
Type the power factor PF, a decimal greater than 0 and at most 1 — typically 0.7 to 0.95 for motor loads, or the value printed on the equipment nameplate. PF = 1 means a purely resistive load.
Press Calculate, read kVA
The apparent power S appears in kilovolt-amps (kVA): S = P / PF. For example, 10 kW at PF 0.8 gives 12.5 kVA. Copy the result to your clipboard, or press Reset to start over.
kW to kVA calculation
- kW to kVA formula
- The apparent power S in kilovolt-amps (kVA) is equal to the real power P in kilowatts (kW), divided by the power factor PF: S(kVA) = P(kW) / PF. For example, 10 kW at a power factor of 0.8 gives 10 / 0.8 = 12.5 kVA.
- What is the power factor?
- The power factor is the ratio of real power (kW) to apparent power (kVA) in an AC circuit: PF = P / S. It is a dimensionless number between 0 and 1 — 1 for a purely resistive load (heaters, incandescent lamps), and lower for inductive loads such as motors and transformers that circulate reactive power.
- Worked examples
- An 85 kW motor load at PF 0.85 needs 85 / 0.85 = 100 kVA of supply capacity. A 7.5 kW load at PF 0.9 draws 7.5 / 0.9 ≈ 8.333 kVA. At PF 1, apparent power equals real power: 3 kW / 1 = 3 kVA. A power factor of 0 is rejected — dividing by it has no physical meaning.
- Why divide by the power factor?
- kVA measures apparent power — the total voltage-ampere product the source must supply. kW measures real power — the portion actually doing work. With reactive (inductive or capacitive) loads the source must supply extra current, so apparent power is larger: S = P / PF, never smaller than P for a valid PF.
- What inputs does the calculator reject?
- Empty or non-numeric fields, negative real power (kW cannot be negative), and any power factor of 0 or outside the range 0 to 1 — PF 0 would mean dividing by zero, and PF above 1 or below 0 is not physically realizable. The result is only produced when both inputs are valid; a validation message tells you which field to fix.
Converting the other way? Use the kVA to kW calculator.
Privacy: every calculation runs in your browser tab — no value you type is sent anywhere. Copy result uses your clipboard only. Results assume sinusoidal steady-state values; verify real installations with a meter.