Amps to Watts (A to W) Conversion Calculator

Use our interactive calculator to easily convert amps to watts (A to W).

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Conversion formula: W = A × V

Or would you rather convert watts to amps?

Amps to Watts Conversion Chart

Here's a chart converting amps to watts at several common DC voltages.

AmpsWatts @ 12 VWatts @ 24 VWatts @ 48 V
1 A12 W24 W48 W
2 A24 W48 W96 W
3 A36 W72 W144 W
4 A48 W96 W192 W
5 A60 W120 W240 W
6 A72 W144 W288 W
7 A84 W168 W336 W
8 A96 W192 W384 W
9 A108 W216 W432 W
10 A120 W240 W480 W
11 A132 W264 W528 W
12 A144 W288 W576 W
13 A156 W312 W624 W
14 A168 W336 W672 W
15 A180 W360 W720 W
16 A192 W384 W768 W
17 A204 W408 W816 W
18 A216 W432 W864 W
19 A228 W456 W912 W
20 A240 W480 W960 W

And here's another chart, this time converting amps to watts at several common AC voltages.

AmpsWatts @ 120 VWatts @ 220 VWatts @ 240 V
1 A120 W220 W240 W
2 A240 W440 W480 W
3 A360 W660 W720 W
4 A480 W880 W960 W
5 A600 W1100 W1200 W
6 A720 W1320 W1440 W
7 A840 W1540 W1680 W
8 A960 W1760 W1920 W
9 A1080 W1980 W2160 W
10 A1200 W2200 W2400 W
11 A1320 W2420 W2640 W
12 A1440 W2640 W2880 W
13 A1560 W2860 W3120 W
14 A1680 W3080 W3360 W
15 A1800 W3300 W3600 W
16 A1920 W3520 W3840 W
17 A2040 W3740 W4080 W
18 A2160 W3960 W4320 W
19 A2280 W4180 W4560 W
20 A2400 W4400 W4800 W

How to Convert Amps to Watts (A to W)

Converting amps to watts is easy, and the formula is the same whether you're working with alternating current (AC) or direct current (DC).

AC power is used in our modern electrical grid, as this type of electricity is easy to transmit over long distances without losses.

The majority of the appliances in your home run on AC power, via a 120V wall outlet that is standard in the US. You may have also noticed a few larger outlets in your home. These outlets are 240V and accommodate appliances that use more power, like an electric range oven or clothes dryer.

DC power, on the other hand, is electricity produced by solar panels or batteries. The phone, tablet or laptop you are reading this on uses DC power, as these devices rely on batteries to operate.

So if you are using solar to power your home, you will also need an inverter with your system. An inverter converts the DC power generated by your solar panels into AC power, that can then be used by appliances via a wall outlet.

To convert amps to watts, multiply amps by volts.

Formula: watts = amps × volts

Abbreviated: W = A × V

Sometimes you'll see this formula written slightly differently, with amps abbreviated as I instead of A and watts abbreviated as P instead of W. The formula itself remains the same, only the abbreviated version changes.

Alternate Abbreviation: P = I × V

Note that this is also called the electrical power formula, which simply states that power equals current times voltage.

Example: DC Voltage

Let's look at a common example using DC power — charging your laptop.

The output rating for a standard MacBook charger is listed as a maximum of 16.5 volts and 3.65 amps. These specs can be found in small print on the side of the charger.

If we look at the side of this laptop charger, we can see that its max DC power output is 3.65 amps at 16.5 volts.

Calculate watts by multiplying volts times amps.

16.5 volts × 3.65 amps = 60.2 watts

This is the amount of power that is received by the battery as it charges. Any laptop charger is also called a power adapter, because it transforms the AC power from the outlet into a DC power source that can be used by the battery.

Example: AC Voltage

Using the same example of a MacBook charger, let's look at the AC side. Also listed on the side of the charger, the input specifications are between 100 volts and 240 volts, at a maximum of 1.5 amps.

The charger's AC input power specifications are a max of 1.5 amps at between 100-240 volts.

Assuming we're using a standard 120 volt wall outlet (in the United States), we can calculate maximum watts by multiplying volts times amps.

120 volts × 1.5 amps = 180 watts

One important thing to note when dealing with charging a battery is that this AC rating is a theoretical maximum, not the amount of power that is continuously drawn from the wall outlet. The actual demand on the charger decreases the more the battery is charged.

Why Convert Amps to Watts?

Converting amps to watts is important for a variety of reasons, especially when dealing with any kind of solar-powered system. You'll want to know how many watts are used by your appliances and devices to make sure that your certain parts of your system -- particularly your inverter -- can handle the total expected wattage.

And when sizing your DIY solar system, you'll need to calculate the wattage all your appliances and then convert watts to watt hours (or watts to kilowatt hours for large solar systems) to estimate your system's total energy consumption.

How to Convert Watts to Amps (W to A)

To convert watts to amps, divide watts by volts.

Formula: amps = watts ÷ volts

Abbreviated: A = W ÷ V

Alternate Abbreviation: I = P ÷ V

Example: DC Voltage

Here's a common scenario where you may want to convert watts to amps. For example, let's say you want to know the maximum current (expressed in amps) produced by a typical residential solar panel rated at 200 watts.

In this case, the manufacturer has also listed a maximum voltage of 17 volts. This is denoted as 'Vmp' in the electrical specifications.

Next, calculate amps by dividing watts by volts.

200 watts ÷ 17 volts = 11.76 amps

So the current produced by your solar panel at full power is 11.76 amps.

Example: AC Voltage

In this next example, let's assume you want to know the current used by your 1,000 watt Ninja blender while it's operating on high.

Your blender plugs into a standard 120 volt wall outlet.

To calculate amps, divide watts by volts.

1000 watts ÷ 120 volts = 8.33 amps

The current required by your blender at full power is 8.33 amps.

How to Convert Volts to Watts (V to W)

Lastly, you may want to convert volts to watts. This formula is also simple.

To convert volts to watts, multiply amps by volts.

Formula: watts = amps × volts

Abbreviated: W = A × V

Alternate Abbreviation: P = I × V

Calculator: Volts to Watts Calculator

Example: DC Voltage

For example, you may want to know the watts of your solar panel — yet you're only given volts and amps.

Let's assume your panel generates a maximum 12 volts at 15 amps. Calculate the watts of your panel by multiplying amps times volts.

15 amps × 12 volts = 180 watts

At maximum power (i.e. maximum sunlight), your solar panel will produce 180 watts.

Example: AC Voltage

Lastly, let's say you want to calculate the watts of your new miter saw you've just purchased for your garage workspace. The saw is rated at 20 amps, and plugs into a standard 120 volt outlet.

Calculate watts by multiplying amps times volts.

20 amps × 120 volts = 2400 watts

More Electricity Calculators

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Amanda Luketa
Amanda Luketa
Amanda is a copywriter and consultant with a research background in solar panel performance. She lives in Colorado.