A lot of people have asked us to determine how many watts are in a 12-volt battery. 12-volt battery wattage is very simple to solve, and we will show you how. On top of that, you can use:
- ‘How Many Watts In A 12V Battery’ Calculator found below. Basically, you just insert the battery capacity in amp-hours (Ah) and the calculator will automatically tell you how many watts there are in that 12V battery.
- 12V Battery Wattage Chart. It’s a table that tells you how many watts are in all 12V battery sizes; from a very small 1000mAh battery to a very enormous 5,000Ah battery.
Let’s clear some things up first:
When we ask about 12V watts, we actually mean watt-hours. Watts and watt-hours are not the same.
Example: How many watts are in a 100Ah 12 volt battery? Such a battery holds 1200Wh. These are 1200 watt-hours. We usually say that a 100Ah 12V battery holds 1200 watts.
1200 watt-hours mean that a battery can do any of the following:
- Produce 1200 watts of power for 1 hour. Example: It can power a 1200-watt air conditioner for 1 hour.
- Produce 600 watts of power for 2 hours. Example: It can run a 600-watt refrigeration for 2 hours.
- Produce 400 watts of power for 3 hours.
- …
- Produce 1 watt of power for 1200 hours (that’s 50 days).

We hope you get the point here (if not, you can use the comments below and we’ll help you out).
Here is how simple it is to calculate how many watts are in a 12-volt battery:
12V Battery Watts = Number of Ah (Amp-Hours) × 12V
Example: How many watts are in an 80Ah 12V car battery? Here is how you can calculate that:
80Ah 12V Car Battery Watts = 80Ah × 12V = 960 Watt-Hours
To help you out, we provide you with a calculator that does this calculation automatically. Further on, you will also find a chart with calculated wattages for 20+ batteries:
How Many Watts In A 12V Battery Calculator
You simply insert how many amp-hours (Ah) battery you have, and the calculator will automatically calculate the wattage (in watt-hours, of course):
Here is how to use this 12V battery calculator:
Let’s say you have a 200Ah 12-volt battery and want to know how many watts there are in a 200Ah battery (voltage: 12V). Simply slide the slider to ‘200’ and you will get the result: 200Ah 12V battery contains 2400 watt-hours (or 2400 watts, as we sometimes say).
This is just one example. The following table will tell you how many watts do different batteries produce:
12V Battery Wattage Chart
Battery Capacity (Amper-Hour or Ah) | 12V Battery Wattage: |
1Ah or 1000mAh | 12 Watts |
2.5Ah or 2500mAh | 30 Watts |
5Ah | 60 Watts |
10Ah | 120 Watts |
15Ah | 180 Watts |
20Ah | 240 Watts |
25Ah | 300 Watts |
30Ah | 360 Watts |
40Ah | 480 Watts |
50Ah | 600 Watts |
60Ah | 720 Watts |
70Ah | 840 Watts |
80Ah | 960 Watts |
90Ah | 1080 Watts or 1.08 kW |
100Ah | 1200 Watts or 1.2 kW |
125Ah | 1500 Watts or 1.5 kW |
150Ah | 1800 Watts or 1.8 kW |
175Ah | 2100 Watts or 2.1 kW |
200Ah | 2400 Watts or 2.4 kW |
250Ah | 3000 Watts or 3 kW |
300Ah | 3600 Watts or 3.6 kW |
350Ah | 4200 Watts or 4.2 kW |
400Ah | 4800 Watts or 4.8 kW |
500Ah | 6000 Watts or 5 kW |
600Ah | 7200 Watts or 7.2 kW |
700Ah | 8400 Watts or 8.4 kW |
800Ah | 9600 Watts or 9.6 kW |
900Ah | 10,800 Watts or 10.8 kW |
1000Ah | 12,000 Watts or 12 kW |
1500Ah | 18,000 Watts or 18 kW |
2000Ah | 24,000 Watts or 24 kW |
5000Ah | 60,000 Watts or 60 kW |
Hopefully, you can use both this table and the calculator above to check how many watts are in your 12V battery. If you need any help with the calculation, you can use the comments below and we’ll help you out.
Can I use 2 x 300 watts, solar panel – Voltage (Vmp)- 17.6V, Current (Imp)- 18A to charge 2 x 12v battery 150ah
Hi Jeremiah, yes, that shouldn’t be a problem.
Hello,
The 80Ah 12v Car battery example calculation used to show how easy it is to do the conversion — is wrong.
The Chart shows 960 watts. Math also would yield that answer–the example shows 1080 watts, which would be applicable for 90Ah battery, not an 80 Ah battery.
I don’t know how long this article has been posted, but when I was admiring the chart and using it to figure out my local power needs, I then read the fine text and discovered that… everything is thrown into doubt since the example described as easy to figure out… is wrong! And no one has posted anything about it since then to point out the error!
At least the math is spelled properly, so there’s that. Unless spellcheck can catch that you meant 90ah instead of 80ah, the text is just going to be used by a chat bot AI in the future and corrupt and deceive people into believing that the Orwellian future of 2+2=5 is true because an authoratitive figure has said so, just like 80*12=1080 when really it’s 960. I just hope I don’t get shocked for pointing this out. (Pun intended.)
Hi Jeff, thank you for pointing this out. This is a great error on our part and we are terribly sorry that we have misspelled those 80Ah and 90Ah. We have fixed the issue, really thank you for pointing it out. That AI implication would be quite funny to see, nice pun, by the way.