Calculate Battery Size For Any Size Inverter (Using Our Calculator)

Pairing a right size capacity battery for an inverter can be a bit confusing for most the beginners

So I have made it easy for you, use the calculator below to calculate the battery size for 200 watt, 300 watt, 500 watt, 1000 watt, 2000 watt, 3000 watt, 5000-watt inverter

Inverter Battery Size Calculator

Note! The battery size will be based on running your inverter at its full capacity


  • Modified sine wave inverter efficiency: 85%
  • Pure sine wave inverter efficiency: 90%
  • Lithium Battery: 100% Depth of discharge limit
  • lead-acid Battery: 50% Depth of discharge limit


  • Inverter runtime: is the total number of hours you would need to run your load on an inverter
  • Inverter input Volts (V): Are you using a 12v, 24v, or 48v solar system?
  • Select a battery type: Select the type of battery you would like to use (Lea-acid, AGM, or Lithium)
𝐈𝐦𝐩𝐨𝐫𝐭𝐚𝐧𝐭 𝐍𝐨𝐭𝐞! If you're not running your inverter at its full capacity, For Example, let's say you have a 1000W inverter but your daily total load at a time doesn't exceed 600 AC watts so instead of entering 1000 in the inverter size box you can enter 600 which will give a battery size according to your load

To recharge your battery from time to time you would need the right size solar panel to do the job! Read the below article to find out the suitable solar panel size for your battery bank

Related Post: Solar Panel Calculator For Battery

How To Calculate Battery Capacity For Inverter

Calculate Battery Size For Inverter

To calculate the battery capacity for your inverter use this formula

Inverter capacity (W)*Runtime (hrs)/solar system voltage = Battery Size*1.15

Multiply the result by 2 for lead-acid type battery, for lithium battery type it would stay the same


Let's suppose you have a 3000-watt inverter with an 85% efficiency rate and your daily runtime is about 5 hours using a 24v solar system

3000*5/24 = 625

Now to cover watt losses when converting DC to AC

625*1.15 (85% inverter efficiency) = 718Ah

How many batteries for 3000-watt inverter

You would need around 24v 150Ah Lithium or 24v 300Ah Lead-acid Battery to run a 3000-watt inverter for 1 hour at its full capacity

Battery Size Chart For Inverter

Here's a battery size chart for any size inverter with 1 hour of load runtime

Inverter Size How Many 100Ah (Lithium) Batteries to run for 1 hour
(100% DoD Limit)
How Many 100Ah (Lead-acid) Batteries to run for 1 hour
(50% DoD Limit)
12v 200 watt0.20.4
12v 300 watt0.30.6
12v 500 watt0.51.0
12v 600 watt0.51.1
12v 1000 watt0.91.8
24v 1000 watt0.40.9
12v 1500 watt1.32.6
24v 1500 watt0.71.4
12v 2000 watt1.83.6
24v 2000 watt0.91.8
24v 3000 watt1.32.6
48v 3000 watt0.71.4
24v 4000 watt1.83.6
48v 4000 watt0.91.8
24v 5000 watt2.24.4
48v 5000 watt1.12.2
24v 6000 watt2.75.5
48v 6000 watt1.32.7
Battery size chart for inverter

Note! The input voltage of the inverter should match the battery voltage. (For example 12v battery for 12v inverter, 24v battery for 24v inverter and 48v battery for 48v inverter


Battery to inverter wire size chart

What size of cable should I use with my inverter and battery?
Inverter wire size chart

Related Posts

I hope this short guide was helpful to you, if you have any queries Contact us do drop a comment below. Thank You!

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Chris Tsitouris is a renewable energy professional with 10+ years of experience as Director of Engineering at Solar Spectrum, previously working as Project Manager at SunPower and Energy Analyst at the National Renewable Energy Laboratory. As a thought leader, Chris has authored numerous articles and research papers.

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