kVA to Watts Calculator
Convert kilovolt-amps (kVA) to watts using power factor: W = kVA × PF × 1,000. Find how many watts a generator, UPS or transformer can supply.
REAL POWER
21,250 W
IN kW
21.25 kW
FORMULA
W = kVA × PF × 1000
💡 How to Convert kVA to Watts
To convert kVA to watts, multiply the kVA by the power factor and then by 1,000. kVA is the apparent power a machine is rated for; watts are the real power available to your appliances. The power factor tells you how much of the apparent power becomes usable watts.
kVA to watts formula
Example: 25 kVA at PF 0.85 → 25 × 0.85 × 1,000 = 21,250 W
Worked examples
- Standby generator rated 7.5 kVA at PF 0.8: 7.5 × 0.8 × 1,000 = 6,000 W.
- 5 kVA inverter at PF 0.9: 5 × 0.9 × 1,000 = 4,500 W.
- 1 kVA UPS at PF 1.0: 1,000 W, as some modern UPS units are rated with equal VA and watts.
kVA to watts table
| kVA | W @ PF 0.8 | W @ PF 0.85 | W @ PF 0.9 | W @ PF 1.0 |
|---|---|---|---|---|
| 1 | 800 | 850 | 900 | 1,000 |
| 2 | 1,600 | 1,700 | 1,800 | 2,000 |
| 3 | 2,400 | 2,550 | 2,700 | 3,000 |
| 5 | 4,000 | 4,250 | 4,500 | 5,000 |
| 7.5 | 6,000 | 6,375 | 6,750 | 7,500 |
| 10 | 8,000 | 8,500 | 9,000 | 10,000 |
| 15 | 12,000 | 12,750 | 13,500 | 15,000 |
| 20 | 16,000 | 17,000 | 18,000 | 20,000 |
| 25 | 20,000 | 21,250 | 22,500 | 25,000 |
| 50 | 40,000 | 42,500 | 45,000 | 50,000 |
| 100 | 80,000 | 85,000 | 90,000 | 100,000 |
Generators: why the 0.8 power factor matters
Diesel generator sets are conventionally rated in kVA at a power factor of 0.8, so a 100 kVA generator delivers about 80 kW of real power. When comparing generators, convert everything to the same unit first so a "10 kVA" and an "8 kW" unit are seen to be the same machine.
Typical power factors: resistive loads such as heaters and incandescent lamps run at 1.0; computer and server power supplies with power factor correction (PFC) run at about 0.95–0.99; induction motors run at roughly 0.8–0.9 at full load and lower when lightly loaded. Diesel generators are conventionally rated at a power factor of 0.8.
Related conversions: watts to kVA · kVA to kW · kVA to amps