Convert Amps To Watts (A to W): Simplest Calculator + Conversion Chart

Amperes (A), volts (V), and watts (W) are the 3 basic electrical units, connecting electrical current, voltage, and power. Every electric device – from air conditioners to washing machines and generators – includes them in their specification sheets.

One of the most common questions here is this: How to convert amps to watts?

To convert amps to watts, we need to use the following formula for electrical power:

P (W) = I (A) * V (V)

In a simple equation, here’s the relation:

Watts = Amps * Volts

To calculate watts, we need both the amperage and voltage (usually either 120V or 220V).

LearnMetrics has prepared handy amps to watts calculator you can freely use. Below the A to W calculator you will also find a table with calculated watts from amps for 120V and 220V voltage systems. To illustrate how amps to watts calculation works, we have also solved 3 examples (scroll down).

Amps To Watts Calculator

 

How Many Amps Are In A Watt?

For easier calculations, knowing how many amps are in a watt is very useful. We start with the original formula for electrical power:

P (W) = I (A) * V (V)

To calculate how many amps are in a watt, we need to specify the voltage. Let’s take the basic 120V. Here’s how we calculate the number of watts in a single amp:

P (W) = 1 A * 120 V = 120 W

As we can see, at 120V, 1 amp is equal to 120 W.

If we use the 220V voltage, we have this amps to watts equation:

P (W) = 1 A * 220 V = 220 W

At 220V, 1 amp is equal to 220 watts.

Here is a full amps-to-watts conversion chart, with solved examples below:

Amps To Watts Conversion Chart

Amps Watts (at 120V): Watts (at 220V):
How many watts in 1 amp? 120 watts 220 watts
How many watts in 2 amps? 240 watts 440 watts
How many watts in 3 amps? 360 watts 660 watts
How many watts in 4 amps? 480 watts 880 watts
How many watts in 5 amps? 600 watts 1100 wats
How many watts in 6 amps? 720 watts 1320 watts
How many watts in 7 amps? 840 watts 1540 watts
How many watts in 8 amps? 960 watts 1760 watts
How many watts in 9 amps? 1080 watts 1980 watts
How many watts in 10 amps? 1200 watts 2200 watts
How many watts in 11 amps? 1320 watts 2420 watts
How many watts in 12 amps? 1440 watts 2640 watts
How many watts in 13 amps? 1560 watts 2860 watts
How many watts in 14 amps? 1680 watts 3080 watts
How many watts in 15 amps? 1800 watts 3300 watts
How many watts in 16 amps? 1920 watts 3520 watts
How many watts in 17 amps? 2040 watts 3740 watts
How many watts in 18 amps? 2160 watts 3960 watts
How many watts in 19 amps? 2280 watts 4180 watts
How many watts in 20 amps? 2400 watts 4400 watts
How many watts in 25 amps? 3000 watts 5500 watts
How many watts in 30 amps? 3600 watts 6600 watts
How many watts in 40 amps? 4800 watts 8800 watts
How many watts in 50 amps? 6000 watts 11000 watts
How many watts in 60 amps? 7200 watts 13200 watts
How many watts in 70 amps? 8400 watts 15400 watts
How many watts in 80 amps? 9600 watts 17600 watts
How many watts in 90 amps? 10800 watts 19800 watts
How many watts in 100 amps? 12000 watts 22000 watts
How many watts in 150 amps? 18000 watts 33000 watts
How many watts in 200 amps? 24000 watts 44000 watts

This is chart is quite easy to use. For example, how many watts is 50 amps? Just consult the chart and you can see that at 120V 50 amps is 6,000 watts and at 220V 50 amps is 11,000 watts.

Let’s solve some real-life examples:

3 Amps To Watts (Example 1)

Let’s say that we have a 5000 BTU portable air conditioner. This is considered a very small air conditioner; it’s powered by only 3 amps.

How many watts does a 3 amp air conditioner use? It’s connected to 120V and we can use the upper amps to watts calculator to figure this out, like this:

3 amps is 360 watts

In short, 3 amps is 360 watts.

15 Amps To Watts (Example 2)

More powerful units, like washing machines and mini-split air conditioners, can be powered by 15 amps. How many watts is that?

Here’s the calculation of 15 amps to watts at 120V:

15 amps is 1800 watts

15 amps are equal to 1800 watts at 120.

If the voltage would be 220V, 15 amps would equal to 3300 W.

100 Amps To Watts (Example 3)

More powerful electrical units can draw as much as 100 amps. For these units, you already need amp breakers. 5 zone mini-split units are a good example of 100 amps electric devices.

They are hooked up to 220V because 120V would need even more current. Here’s the conversion of 100 amps to watts:

100 amps is 22000 watts

This is a massive 22,000 W device at 100 amps.

If you have a specific example in mind, you can post it in the comments below and we’ll solve it together.

10 thoughts on “Convert Amps To Watts (A to W): Simplest Calculator + Conversion Chart”

  1. If we use the 220V voltage, we have this amps to watts equation:

    P (W) = 1 A * 120 V = 220 W

    At 220V, 1 amp is equal to 120 watts.

    seeing the last line above on google is how i came to your site.

    Reply
  2. Hello, I have 4 led drivers to be connected via a 2 pin socket that converts to a 12DC current to power a maximum 60watt led strip. Plan was to run 4 switch lives from a wall switch in the kitchen to the the 4 locations of the drivers. Can that circuit from the consumer unit be a 5amp circuit with a 6amp breaker?

    Reply
    • Hello there, 6 amp breaker can handle 5 amp circuit. Given that you have 60W led strip and 12V voltage, that will require a max. 5 amp current to run. So, all in all, this should be ok.

      Reply
  3. The above examples provide watts but what is the time duration? I am trying to figure out the following. I have a 1 amp draw at 120 volts. Running 24 hours for 30 days. What would be the kwh for this device over a months time?

    Reply
    • Hi Dennis, we have seen your comment and immediately published an article that will help you out. Basically, you are looking to convert watts to kilowatts (here is this watts to kWh article).

      Basically, you have a 120 watt (1A × 120V = 120W) device. You run it for 24h × 30 = 720 hours. To get the kWh from watts, you multiply 120 watts by 720 hours and divide by 1000 (because 1 kW = 1000 W). Here is the result: 86.40 kWh. In short, such a unit will consume 86.40 kWh of electricity. Hope this helps.

      Reply

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