Power converter

Watts to Amps Calculator

Find current in amps from power in watts and voltage — DC, AC single-phase, or three-phase.

How Watts to Amps works

Amps measure electric current, watts measure power, and volts measure potential. For a DC circuit the relationship is simply current = power ÷ voltage (I = P ÷ V).

AC circuits add a power factor, and three-phase systems add a √3 factor. This calculator handles all three so you can size wiring, breakers, and chargers correctly.

Formula

1I(A) = P(W) ÷ V(V) (DC)DC

2I(A) = P(W) ÷ (V × PF) (AC single phase)1Φ

3I(A) = P(W) ÷ (√3 × V × PF) (AC three phase)3Φ

PF is the power factor (1 for purely resistive loads, ~0.8 for many motors).

Watts to Amps conversion table

Reference Table6 rows

Watts to amps at common voltages (DC / resistive, PF = 1).
Power↕	At 12 V↕	At 120 V↕	At 240 V↕
100 W	8.33 A	0.833 A	0.417 A
500 W	41.67 A	4.17 A	2.08 A
1,000 W	83.33 A	8.33 A	4.17 A
1,500 W	125 A	12.5 A	6.25 A
2,000 W	166.7 A	16.67 A	8.33 A
3,000 W	250 A	25 A	12.5 A

💡 Click any row to auto-fill the calculator aboveClick column headers to sort

FAQ: Watts to Amps

How do you convert watts to amps?

Divide power in watts by voltage in volts: amps = watts ÷ volts. For AC, also divide by the power factor; for three-phase, divide by √3 × volts × power factor.

How many amps is 1500 watts at 120 V?

On a 120 V DC or resistive circuit, 1,500 W ÷ 120 V = 12.5 amps.

What is power factor?

Power factor is the ratio of real power to apparent power in an AC circuit. Resistive loads are about 1.0; motors and many electronics are around 0.8.

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