How Many Amps Does A Generator Produce? (500W to 30kW Generators)

With a generator, we usually just get the wattage. Example: 5kW generator, 22kW generator, and so on. We don’t really know how many amps does a generator put out. To help everybody out, we’ll look into how to calculate how many amps does a generator produce.

Below, you will also find a ‘Generator Amps Calculator‘ and a calculated table of how many amps do generators draw at 220V and 240V voltage (500W to 30kW generators).

Here’s are two pieces of information that you will need if you want to find out the amps any generator produces:

  1. Wattage. This is easy to find out; pretty much everybody knows how many watt generator they have. Example: 10,000W generator.
  2. Voltage. This is the electric potential; usually 220V, or in the case of big generators, 240V.

This is all you need to determine how many amps does your generator draw. We are going to look into how to calculate the amps by hand (using the basic electric power equation) for a 5,000W Honda generator.

Further on, you will also find the ‘Generator Amps Calculator’ and the calculated table to help you out determine the amperage of your generator.

How To Calculate How Many Amps Does A Generator Draw?

If you know the wattage and voltage of your generator, you can quite easily use the electric power equation to calculate the amps. Here’s the equation:

P (power) = I (current) × V (voltage)

To better illustrate how to use this equation, let’s use electric units instead of power, current, and voltage:

Watts = Amps × Volts

To calculate the amps, we need to express the amps like this:

Amps = Watts ÷ Volts

If you want to calculate amps generator draws, you need to divide watts by volts. Simple, right? Let’s do 1 example before we check out the automatic ‘Generator Amps Calculator’.

Example: How many amps does a Honda 5,000W generator produce at 220V?

We know both the wattage (5,000W) and the voltage (220V). Here’s how we can calculate the amps based on these two figures:

Amps = 5,000W ÷ 220V = 22.73 Amps

In short, Honda 5,000W generator produces 22.73 amps.

To make things even easier, you can use the before-mentioned watts to amps calculator for generators:

Generator Amps Calculator

You just insert (or use the slider) wattage and voltage, and the calculator will dynamically calculate the amps such a generator produces. You can also play around with numbers a bit to see how this calculation works:


You can check the above 5,000W Honda generator amperage. If you slide ‘Wattage’ to 5,000W and ‘Voltage’ to 220V, you will get the result ‘22.73 Amps’, the same as in our example above.

Here is the promised calculated table for ampacity of 500W to 30kW generators:

Ampacity For 500W To 30kW Generators (Calculated Table)

Generator Wattage: Amps at 220V: Amps at 240V
500W generator: 2.27 Amps 2.08 Amps
1,000W generator: 4.55 Amps 4.17 Amps
1,500W generator: 6.82 Amps 6.25 Amps
2,000W generator: 9.09 Amps 8.33 Amps
2,500W generator: 11.36 Amps 10.42 Amps
3,000W generator: 13.64 Amps 12.50 Amps
3,500W generator: 15.91 Amps 14.58 Amps
4,000W generator: 18.18 Amps 16.67 Amps
4,500W generator: 20.45 Amps 18.75 Amps
5,000W generator: 22.73 Amps 20.83 Amps
6,000W generator: 27.27 Amps 25.00 Amps
7,000W generator: 31.82 Amps 29.17 Amps
8,000W generator: 36.36 Amps 33.33 Amps
9,000W generator: 40.91 Amps 37.50 Amps
10,000W generator: 45.45 Amps 41.67 Amps
11kW generator: 50.00 Amps 45.83 Amps
12kW generator: 54.55 Amps 50.00 Amps
13kW generator: 59.09 Amps 54.17 Amps
14kW generator: 63.64 Amps 58.33 Amps
15kW generator: 68.18 Amps 62.50 Amps
16kW generator: 72.73 Amps 66.67 Amps
17kW generator: 77.27 Amps 70.83 Amps
18kW generator: 81.82 Amps 75.00 Amps
19kW generator: 86.36 Amps 79.17 Amps
20kW generator: 90.91 Amps 83.33 Amps
21kW generator: 95.45 Amps 87.50 Amps
22kW generator: 100.00 Amps 91.67 Amps
23kW generator: 104.55 Amps 95.83 Amps
24kW generator: 109.09 Amps 100.00 Amps
25W generator: 113.64 Amps 104.17 Amps
26kW generator: 118.18 Amps 108.33 Amps
27kW generator: 122.73 Amps 112.50 Amps
28kW generator: 127.27 Amps 116.67 Amps
29kW generator: 131.82 Amps 120.83 Amps
30kW generator: 136.36 Amps 125.00 Amps

If you still didn’t find the answer, you can pose a question in the comments below and we’ll try to help you out.

2 thoughts on “How Many Amps Does A Generator Produce? (500W to 30kW Generators)”

  1. My distribution center from the power co says 400 amps on the main breaker. (1 phase) To determine generator size, do I multiply 400 by 120 or 240?
    Thnank you.

    • Hi Alan, well, it all depends on the voltage in the circuit. If you have a standard 120V voltage, multiply by 120. If you have an upgraded 240V voltage, multiply by 240.

      Be sure to remember that a 400 amp breaker can be loaded up to 80% of its capacity at most, in accordance with the NEC 80% rule. So, it can handle 320 amps of current. The breaker doesn’t really care if this is a 12V battery voltage of a big 240V voltage. Hope this helps a bit.


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