Enter horsepower and power factor to calculate the apparent power (kVA) needed to supply that motor.
How to Use the Horsepower to Kilovolt-Amps (kVA) Calculator
Two fields only: horsepower and power factor. No voltage, no current, no phase — kVA and HP scale together regardless of how a motor is wired, so the ratio between them depends purely on power factor.
Getting from a mechanical rating to an apparent-power figure is really two conversions stacked into one: horsepower to real power (kW), and real power to apparent power (kVA). This calculator folds both into a single formula rather than making anyone run them one at a time:
HP → kW: kW = (HP × 745.7) ÷ 1000
kW → kVA: kVA = kW ÷ PF
Combined: kVA = (HP × 745.7) ÷ (1000 × PF)A 20 HP motor at a 0.85 power factor needs 17.55 kVA of apparent capacity to deliver that mechanical output — noticeably more than the 14.91 kW of real power the motor alone would suggest, because a generator, UPS, or transformer feeding it has to supply the full apparent load, reactive portion included.
Sizing backup power or a transformer for motor loads is exactly where this calculator earns a spot on its own page rather than being folded into a general horsepower converter — a generator spec sheet nearly always states capacity in kVA, while a motor nameplate states output in HP, and nothing in either document does the unit-crossing math for you.