kWh To Ah Conversion (Calculator: Input kWh And V, Get Ah or mAh)

How do I convert kilowatt-hours to amp-hours?

In many cases, we need to convert kWh to Ah. With smaller 12V batteries, we also need to convert kWh to mAh.

We will look into how does kWh to amp-hours (Ah) conversion. You will also find a kWh to Ah calculator that dynamically calculated kWh from Ah and a calculated table of kWh to Ah and kWh to mAh. Let’s start with an example to illustrate.

Example: How to convert 13.5 kWh to Ah? First, we need to specify the voltage. Let’s say we have a 12V battery. We can calculate Ah from kWh using the basic kilowatt-hour equation:

kWh = Ah × V × 1,000

We express amp-hours (Ah) and insert our numbers:

Ah = kWh ÷ V × 1,000

Ah = 13.5kWh ÷ 12V × 1,000 = 1,125 Ah

That means that 13.5 kWh is equal to 1,125 Ah or 1,125,000 mAh on a 12V circuit.

Here is the kWh to Ah calculator that makes this calculation automatically:

kWh To Ah Calculator

Just insert kWh and voltage (V), and you will get the calculated Ah. You can also play around with numbers a bit and the calculator will dynamically calculate the ampere-hours:


For example, it is useful to know this basic conversion:

1 kWh to Ah in a 12V battery is equal to 83.33 Ah.

On the other hand, if you need an Ah to kWh conversion, you can find a similar Ah to kWh conversion calculator here.

Here is the full calculated table of kWh to Ah conversions for the 12V circuit:

kWh To Ah And kWh to mAh Chart (At 12V; For Batteries)

kWh (kilowatt-hours) Ah (amp-hours) mAh (milliamp-hours)
0.01 kWh 0.83 Ah 830 mAh
0.02 kWh 1.67 Ah 1,670 mAh
0.025 kWh 2.5 Ah 2,500 mAh
0.05 kWh 4.17 Ah 4,170 mAh
0.1 kWh 8.33 Ah 8,330 mAh
0.5 kWh 41.67 Ah 41,670 mAh
1 kWh 83.33 Ah 83,330 mAh
2 kWh 166.67 Ah 166,670 mAh
10 kWh 833.33 Ah 833,330 mAh
20 kWh 1,666.67 Ah N/A
50 kWh 4,166.67 Ah N/A
100 kWh 8,333.33 Ah N/A

If you have any questions about how to convert these two electrical units, you can pose a question in the comments and we’ll help you out.

8 thoughts on “kWh To Ah Conversion (Calculator: Input kWh And V, Get Ah or mAh)”

  1. I am trying to determine how many Ah 12V battery I will need to power my 115VAC refrigerator for 48 hours.
    I used a watt meter and found that my frig uses 1.04 kWh in 48 hours.

    If I use an inverter that is 90% efficient I am coming up with approximately 91Ah of 12V battery. Does that seem correct?

    • Hello Brent, if your fridge uses 1.04 Wh in 48 hours, you basically need a battery that can produce 1.04 kWh of output. That would be 1040 Wh/12V = 86.7Ah battery (at 100% battery efficiency). Of course, you also have to account for 90% efficiency.

      That 1.04 kWh should represent 90% of the battery capacity. Here is how you account for that: 86.7 Ah / 0.9 = 96.3Ah. So, you would need at least a 96.3Ah 12V battery. That’s practically your standard 100Ah battery. Hope this helps.

  2. Hi,
    I power 2 led lights of 72watts @ 220v. If a run these on battery setup of 24V with inverter how much will a 100Ah battery last…?

    • Hello there, so 2 LED lights with 72W each required a total of 144W power. A 12V 100Ah has a capacity of 1,200Wh and will run both of them for 1,200Wh/72W = 16.7 hours. If you have a 24V 100Ah battery, it will have double the capacity (2,400Wh) and will run the lights for double the time (33.3 hours). Hope this helps.

  3. Hello I have a solar system 8 panels; inverter and 4 battery (200A each) for night
    Can I keep the fridge (730kwh/year) all night in power without damaging the battery
    Thanks for your help

  4. Hi
    Please I want to know the difference between lithium battery rated in kWh and tubular batteries rated in ah and their application in designing a solar inverter system

    • Hi there, that’s completely understandable. The battery capacity should always be expressed in watt-hours (Wh) or kWh. That’s the ‘real’ capacity. In most cases, however, battery capacity is expressed in amp-hours (like your tubular batteries).

      You have to put both batteries on the same denominator, and the kWh is the best unit for that. Here’s how you can do that: Let’s say you have 1000 Ah tubular batteries that run on a 12V DC current. To get the Wh, you simply multiply the Ah by voltage and you get 12,000 Wh capacity. This is a 12 kWh capacity. If you have lets say 10 kWh lithium battery, you can now compare these two battery capacities apple-to-apple. Hope this makes sense.


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