What is the Difference Between UPS and Inverter?

By:Michael Johns

inverter vs ups

Trying to understand the difference between a UPS and an Inverter?

I’m not surprised if you’re a little confused.

There’s a lot of misleading, complicated, and incorrect information out there.

And you don’t want to use the wrong piece of equipment as they are two very different things!

That’s why I thought it important to write this easy-to-understand guide to UPS vs Inverters.

Below we’ll go through inverters and UPS in simple terms, including how they work, the pros and cons of each, and the key differences.

Once you’ve finished reading, you’ll know exactly which is best for you – inverter or UPS?

So let’s jump in.

What is an Inverter?

A power inverter is used to convert Direct Current (DC) into Alternating Current (AC). 

DC is the power you get from a battery and AC is the power you need to run most appliances and electronics.

You connect an inverter to a battery, like a car or deep cycle battery, in order to convert the current into a useable current for your appliances. Once you hook up an inverter to a battery you can then plug your electronic devices into the inverter to run them.

An inverter is not a power source on its own and needs a separate power supply to operate. They are most often used with RV, trucks, and car batteries in order to generate off-grid electricity. You will also find them used with solar panels in order to convert DC into AC.

An inverter can help you to deliver power for as long as your battery has energy. Plus you can get them in a wide range of sizes from small 100 watt to over 5000 watt capacity.

Example of power inverter
An example of a power inverter

What is a UPS?

UPS stands for uninterruptible power supply. It is an electrical backup to deliver emergency power during a power outage or the failure of an input power source.

The big benefit to a UPS is that it provides instant protection from an electricity failure. This is because its batteries kick in and deliver electricity to your electronics as soon as power disappears from the main electricity source.

Example of a UPS

Generally, a UPS is used with computers, data centers, and telecoms equipment. It gives power for a short amount of time, such as 5 – 15 minutes. This gives you enough time to protect your systems until mains electricity is restored. Or to save information to prevent data loss.

You can get UPS in a wide range of sizes from enough power for a single computer to industrial capabilities for manufacturing processes. 

There are three types of UPS – online, offline, and line interruption.

Main Differences Between Inverter and UPS


The reason you would use an inverter or UPS is different. A UPS is best used when trying to protect equipment like computers and servers. They are particularly good if you experience regular short-term power cuts. With the right UPS, you can keep a system online for half an hour without ever losing electricity. This makes UPS brilliant for offices and commercial settings where to stop data loss and keep businesses functioning.

An inverter is another great way to produce backup AC power but it will not kick in automatically during a power outage. You will have to manually switch on and hook up your electronics to the inverter. While it is slower to use, you will be able to generate power for longer periods as you can connect an inverter to larger and multiple batteries. Quite often, inverters are used for off-grid electricity in RVs, cabins, boats, and solar panel systems.

Ease of Use and Maintenence

Once installed a UPS is pretty much maintenance-free and doesn’t require anything else to operate. It is one neat package that includes any required battery supply and cables already installed. One downside is that the battery of a UPS is constantly being charged and discharged as it is being used all the time. 

Inverters can be a little more of a faff. This is because you need other equipment to make it work such as a separate battery. You will need to wire the inverter to the battery and ensure the battery is well maintained. For example, you must ensure a deep cycle battery remains charged and even filled with distilled water. Your inverter should last forever is well cared for, plus your battery will last longer as it is not always in use.


So how much does an inverter cost and how much does a UPS cost?

Well, it all depends on what you need in terms of power. You can usually get a more powerful inverter for your money. For example, for $200 you could get yourself a decent 1000W inverter while only getting a 600W UPS.

Don’t forget, that you’ll also need to spend at least $150 on a battery to go with your inverter so the difference is not that much. 

Comparison Chart of UPS and Inverters

Here’s a handy chart to quickly show you the differences between an inverter and UPS.

FunctionConverts DC to ACDelivers electricity when mains power fails
BatteryExternal (Sold separately)Built-in
UsageCommercial / Keep computers running to avoid data lossOff-grid electrical systems e.g. RV or solar panel.
CostCheaper but you need to buy a batteryMore expensive but all-in-one solution
Run TimeHoursLess than 30 minutes
Voltage FluctuationYesNo

Final Words on UPS vs Inverter

The difference between a UPS and an Inverter is pretty simple.

A UPS connects to your electrical grid, stores electricity in a battery, and delivers power when the mains power fails.

An inverter just converts DC to AC power and needs to be connected to an off-grid energy source like a battery.

A UPS essentially includes the function of an inverter built-in with a rectifier that converters power within the UPS internal circuits.

If you’re looking for a way to keep your office computer online to protect data then a UPS is perfect to stop any failure in electricity. For a more off-grid solution, then an inverter is an essential piece of your equipment.

For more options when it comes to electricity backups read Inverter vs Generator: Is an inverter better than a generator?