Watt Value Calculator

300 Watts to Amps Calculator

Find the current in amps for a 300 watt load. Select the circuit voltage and system type below — DC, single-phase AC, or three-phase AC — and the calculator shows the result instantly. The table below lists results at common voltages.

Conversion direction
Electrical system
Quick voltage presets
Calculated result1000 W · 120 V · DC
8.333 A
Formula usedI = P / V

Custom voltage is always supported.

300 Watts to Amps — Conversion Table

Results at common voltages. AC values use power factor = 0.9.

300 watts to amps at various voltages
VoltageDC (I = P/V)AC 1φ (PF 0.9)AC 3φ (PF 0.9)
12 V25 A27.7778 A16.0375 A
24 V12.5 A13.8889 A8.0188 A
48 V6.25 A6.9444 A4.0094 A
120 V2.5 A2.7778 A1.6038 A
240 V1.25 A1.3889 A0.801875 A

Formulas Used

DCI = P / V

No power factor needed for DC circuits.

AC 1φI = P / (V × PF)

Single-phase AC — multiply voltage by power factor.

AC 3φI = P / (√3 × V × PF)

Three-phase AC — divide by √3 ≈ 1.732.

Frequently Asked Questions

How many amps is 300 watts at 120V?

DC or resistive: 300 / 120 = 2.5 A. Single-phase AC at PF 0.9: 300 / (120 × 0.9) = 2.7778 A.

How many amps is 300 watts at 240V?

DC or resistive: 300 / 240 = 1.25 A. Single-phase AC at PF 0.9: 300 / (240 × 0.9) = 1.3889 A.

How many amps is 300 watts at 12V?

DC: 300 / 12 = 25 A. This is common for 12V battery and solar systems.