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How Many Amps is 1000 Watts? – Answered

Written by Edwin Jones / Fact checked by Andrew Wright


Are you planning to get a 1,000-watt clothes dryer or pressure cooker? If so, you must know the appliance’s amp draw to help you determine your property’s power usage. But how many amps is 1,000 watts?

A 120-volt 1,000-watt device typically has an 8.33-amp rating. Note that this measurement may differ among electronic units, especially for different current types.

Here, you’ll learn how to calculate the amperage rating of 1,000 watts based on the current types.

Calculating Amps From 1000 Watts

As mentioned earlier, figuring out 1,000 watts equals how many amps requires looking into the current type used. The two major kinds of current are direct current (DC) and alternating current (AC).

Each current type uses a different formula for calculating the amps of a 1,000-watt device. You can find the formulas to use for each current type below:

1. Watts-to-Amps Conversion for DC

DC is the flow of electricity that doesn’t change direction. Its power is generally produced by sources like batteries, generators, and fuel cells. This current type uses the following formula to determine the amperage:

\[ \text{Amps} = \frac{\text{Watts}}{\text{Volts}} \]

For instance, your appliance requires 220 volts. Using the formula mentioned above, the amp rating of that 1,000-watt unit is:

\[ \text{Amps} = \frac{1000}{220} = 4.55\, \text{amps} \]

Here’s another example: assuming you have a 1,000-watt electronic device at 120 volts, the amp draw of that unit using DC is:

\[ \text{Amps} = \frac{1000}{120} = 8.33\, \text{amps} \]

2. Watts-to-Amps Conversion for AC

AC has two subtypes: one-phase (single-phase) and three-phase. The difference between the two is their power distribution.

Single-phase AC typically has a voltage that rises and falls constantly. On the other hand, the standard three-phase circuit still has a constant voltage, but it’s split three times in one cycle.

Additionally, each AC subtype uses a different formula to determine a 1,000-watt device’s amperage.

One-phase AC


For the single-phase AC, use the following formula:

\[ \text{Amps} = \frac{\text{Watts}}{\text{Power Factor} \times \text{Voltage}} \]

Since the power factor of a one-phase current never exceeds 1, let’s assume that the PF is 1. In such a case, a 1,000-watt appliance using 12 volts in a single-phase AC will have an amp rating of:

\[ \text{Amps} = \frac{1000}{1 \times 12} = 83.33\, \text{amps} \]

Three-phase AC


The formula for the device in a three-phase AC depends on its use of line-to-line or line-to-neutral voltage.

  • The formula to use if it’s using line-to-line voltage is the following:

\[ \text{Amps} = \frac{\text{Watts}}{\sqrt{3} \times \text{PF} \times \text{Voltage}} \]

As the power factor in a three-phase AC is usually unity (one), we can calculate that the drawn current of a 1,000-watt appliance at 240 volts is:

\[ \text{Amps} = \frac{1000}{\sqrt{3} \times 1 \times 240} = 2.4\, \text{amps} \]

  • On the other hand, use the formula below to find the amperage of your 1,000-watt electronic unit in a three-phase AC using line-to-neutral voltage:

\[ \text{Amps} = \frac{\text{Watts}}{3 \times \text{PF} \times \text{Voltage}} \]

Using the same values as an example, the 1,000-watt device connected to a 240-volt source on a line-to-neutral voltage will draw:

\[ \text{Amps} = \frac{1000}{3 \times 1 \times 240} = 1.39 \]

Remember, manually calculating is not the only option to convert watts to amps. You may use an online calculator for help in this regard.

Watts-to-Amps Conversion Table

Here’s a table to aid you in quickly checking the amperage rating of a 1,000-watt electronic device based on different voltages.

Voltage DC Single-Phase AC Three-Phase AC (Line-to-Line Voltage) Three-Phase AC (Line-to-Neutral Voltage)
12 83.33 amps 83.33 amps 48.11 amps 27.78 amps
110 9.09 amps 9.09 amps 5.25 amps 3.03 amps
120 8.33 amps 8.33 amps 4.81 amps 2.78 amps
150 6.67 amps 6.67 amps 3.85 amps 2.22 amps
220 4.54 amps 4.54 amps 2.62 amps 1.51 amps
240 4.17 amps 4.17 amps 2.41 amps 1.39 amps


Remember, your first task is to determine the current type of your device to find out how many amps is 1,000 watts. Then, use the appropriate formula based on your initial findings.

Don’t forget that certain current types have sub-categories, especially the three-phase AC. Also, this particular current type requires different calculations based on the kind of voltage used. Confirm these details first, and you can arrive at the correct answer.

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