Amps to kVA Calculator
Convert electrical current (Amps) to Apparent Power (kVA). Use this tool to properly size generators, transformers, and UPS systems.
Circuit Details
Apparent Power
Amps to kVA Conversion Guide
To size a generator correctly, you need to know the total Apparent Power (kVA) your system requires. While appliances are often rated in Amps, generators are rated in kVA.
Single-Phase Formula
Standard household (120V/240V)
Three-Phase Formula
Industrial / Commercial (208V/480V)
Why calculate kVA instead of kW?
Kilowatts (kW) measure the power that actually does work (Real Power). kVA measures the total power being pushed through the system (Apparent Power), including inefficiencies. Since generators must handle the total load, kVA is the critical number for sizing the alternator and breakers to prevent overheating.
Common Amps to kVA Chart (at 240V / 480V)
| Amps | Single-Phase (240V) | Three-Phase (480V) |
|---|---|---|
| 20 A | 4.8 kVA | 16.6 kVA |
| 30 A | 7.2 kVA | 24.9 kVA |
| 50 A | 12.0 kVA | 41.6 kVA |
| 100 A | 24.0 kVA | 83.1 kVA |
| 200 A | 48.0 kVA | 166.3 kVA |