Power Calculator
Calculate watts, amps, and volts for single-phase and three-phase supplies. Tally up equipment loads and check breaker requirements.
Single-Phase Power
Enter any two known values to solve for the third. Power = Voltage × Current.
V
A
W
Presets:
Enter any two values to calculate.
Voltage
—
Current
—
Power
—
Three-Phase Power
P = √3 × VL × IL × PF. Enter any two of voltage, current, or power (plus power factor) to solve for the third.
V
A
W
PF
Presets:
Enter any two values (plus PF) to calculate.
Line Voltage
—
Line Current
—
Total Power
—
kVA (Apparent)
—
Load Tally
Add up equipment wattages to see the total load and current draw at a chosen voltage.
V
| Equipment | Watts | Qty | Subtotal | |
|---|---|---|---|---|
| 2,000 W |
Total Power
—
Total Current
—
Suggested Breaker
—
Load (kW)
—
Quick Reference
Maximum wattage for common breaker sizes at typical supply voltages.
| Breaker (A) | @ 120 V | @ 230 V | @ 240 V | @ 400 V (3φ) |
|---|