Best 4000 Watt Generators

You’ve done all of the power calculations of your appliances - now it’s time to buy a 4000 watt generator to run them all.

Of course, if you haven’t bought a generator before it can be a little frightening.

After all, there are so many things to consider.

Thankfully, there are a lot of great 4000 watt generators on the market.

If you are feeling a little overwhelmed by the amount of choice, then we’re here to help.

Here are just a few of the best 4000 watt generators on the market.

We’ve also written a buyer’s guide to help you to make a decision that much more easily.


Champion Power Equipment 100302 4000-Watt RV Ready Open Frame Inverter, Yellow

The Champion 4000 Watt RV Ready Open Frame Inverter is ideal if you want a great generator for an emergency or to power up your RV.

As far as power goes, it has a respectable 4000 surge watts and 3500 running watts. 

Furthermore, the generator lasts for around 17 hours as the gas tank has a capacity of 2.9 gallons. This is perfect if you need power that lasts a long time in an emergency.

The device will tell you when its oil is low, as it has a sensor. This will automatically turn the unit off if the oil levels drop to an unacceptable level, protecting your engine in the long run. It’s not super noisy either.

The unit comes with a range of different outlets, including a dual USB adapter that you can use to charge your smaller devices such as your smartphone.

With a 3 year warranty and lifetime technical support, you really can’t go wrong with this device.

While the device isn’t very noisy, it isn’t the quietest option out there either, so it may be a little too loud for certain camping areas. 

This is something to keep in mind if you are planning on using the generator while camping or RVing.


  • 3 year warranty
  • Long runtime
  • Good value for money


  • The noise may not be acceptable for certain camping areas


Westinghouse Outdoor Power Equipment 4500 Peak Watt Super Quiet Portable Inverter Generator, Remote Electric Start with Auto Choke, Wheel & Handle Kit, RV Ready, Gas Powered, Parallel Capable

If you’re in the market for a generator that is both powerful yet quiet, you are in luck with the Westinghouse iGen4500.

This generator is more than sufficient to bring your appliances in your RV to life. It has 3700 running watts, and is capable of getting up to 4500 starting watts.

To run the generator, you just need a suitable amount of gasoline. It has a fuel capacity of 3.4 gallons in total, and can run for a whopping 18 hours.

If you want to see your generator’s data, you just need to check the LCD display. This will show you the amount of power that the generator is currently producing, how much run time it has remaining, its voltage and the amount of fuel.

Moving it around is pretty simple too, as it comes with a telescoping handle. The generator is super quiet too, running at 53 decibels.

It comes with an RV outlet so you can automatically hook it up to your RV without buying any extra adapters.

The USB outlets make a welcome addition too, allowing you to charge your smartphone in no time. If that wasn’t enough, you will even get a 3 year Westinghouse warranty. It is a little bit heavy though.


  • Quiet
  • Long run time
  • LCD display - shows you all of your key data
  • Easy set up


  • Somewhat heavy


DuroMax XP4400E Gas Powered Portable Generator-4400 Watt Electric Start-Camping & RV Ready, 50 State Approved, Blue/Black

Looking for plenty of power? Look no further than the Duromax XP4400E. This gas powered generator has an impressive 3.96 gallon fuel capacity, and it can run for around 12 hours at 50% capacity.

Thankfully this generator can be used wherever you go, including in national parks and in California.

It’s pretty heavy, but this isn’t too much of an issue as it comes with a handle and wheels which makes it easier to maneuver. To start it, you need to use a turnkey.

The generator comes with 3 different outlets in total, more than enough to fire up most of your key electrical items.

It has 4400 starting watts and 3500 running watts. It even comes with a sparkplug wrench, a toolset, some DC cables and an oil funnel.

You cannot use it to charge any electronics that are particularly sensitive, however.


  • 4400 surge watts
  • Decent run time
  • Comes with lots of extra accessories


  • Can’t be used to charge sensitive electronics


WEN GN400i RV-Ready 4000-Watt Open Frame Inverter Generator, CARB Compliant, Black/orange

If you are looking for a lightweight generator that still provides plenty of power, the WEN GN400i is a good choice. This generator is ideal for running sensitive electronics, and it weighs fairly little at only 70.5 lbs.

The generator has an output of 4000 surge watts and 3500 running watts. It also has parallel connection functionality, which allows you to connect it to another WEN GN400i generator to get even more power output.

It has a 1.85 gallon tank, and a running time of around 7 hours. If you’re curious about how your generator is doing, then you can easily view that information.

There is an indicator light that will inform you when more fuel is needed, or if there’s a charging issue. 

The generator is pretty quiet at around 57 decibels, so this is great for campgrounds that may not allow very loud generators.

The generator comes with a 2 year manufacturer warranty, and the brand even provides technical support to all of its customers.

The biggest issue is with the slightly shorter run time, which means you will need to refuel more regularly. It’s pretty affordable though, so it’s great if you’re on a budget. 


  • Quiet operation
  • Parallel capabilities
  • Lightweight
  • Affordable


  • Short run time


Firman P03601 Portable Generator, 3650-Watt, Recoil Start, 14 Hour Run Time - Quantity 1

For a reliable power source, you can’t go wrong with the Firman P03601. This generator is ideal for all sorts of purposes, such as for camping in your RV and for job sites. It’s lso quite effective in emergency situations.

The generator will give you 4550 starting watts, and 3650 running watts which is pretty impressive for a generator of this size.

In addition, it also comes with a Firman Volt Lock, and this helps to ensure that the voltage is well regulated so your power is consistent. It has a capacity of 5 gallons, and this means that it can run for up to 14 hours in total.

The generator is somewhat heavy at 110 lbs, and it doesn’t help that it doesn’t come with any wheels. It is pretty easy to get it start though - all you have to do is press a button.

It comes with 4 different outlets in total, in addition to oil, a spark plug wrench and a funnel. 


  • Remote start - perfect for extra convenience
  • 14 hours run time
  • Comes with additional accesories
  • 5 gallon fuel capacity
  • Easy to use


  • It’s quite heavy and doesn’t come with any wheels

Best 4000 Watt Generators Buying Guide

What Can a 4000 Watt Generator Power?

You may be wondering why you should get a 4000 watt generator in specific. Well, to put it simply, with a 4000 watt generator you can power pretty much all of your key appliances inside of an RV.

You should be operating your air-conditioner, refrigerator and your lighting, plus a few other things without much problem. 

They’re not just good for RVs - they’re also a good back up power source for your home. At home, you can use these generators to run your refrigerator and freezer, in addition to a couple of extra things.

It’s certainly not enough power to keep your whole house up and running, but it will give you the essentials in case of emergency. 

Things to Consider

It’s important to know how you can pick the ideal 4000 watt generator for you.

Not every model is made equally, and as a result, not every model will give you what you need.

These are just a few of the main features that you should think about before you hit the buy button.


The engine of your generator is certainly one of the key things that you need to think about.

You can get a range of different fuels to run a generator engine, but the most popular are propane and gasoline. These these change the fuel into the electrical energy needed to power the gadgets in your home. 

As you may imagine, if the engine of your generator is more powerful, then it’s going to give you more power. You should be looking for a generator that has around a 212cc or 224cc engine.

Starting and Running Watts

Generators provide what is known as starting watts and running watts. It’s important to understand what both of these terms mean before you buy your device.

Essentially, running watts are what your appliances need to run on a consistent basis. Starting watts are slightly difference. When you first hook up an electronic device to a power source, they may need a tiny bit of extra power when they first start, and these are the starting or surge watts.

You will need to think about the amount of power that you need for all of your devices - total up the number of watts needed to keep your appliances running, and add up the number of watts needed to get them started.

Then check whether your generator of choice has specifications that match your requirements.


The vast majority of 4000 watt generators will run on gasoline, as this is the most popular fuel type.

The generators usually have a tank capacity of roughly 3.4 to 4 gallons. Naturally, the larger the capacity, the longer the device will be able to run. This does sometimes depend on how efficient the generator is with fuel.

If you need your device to last longer then you will need to think about getting a generator with a larger fuel tank capacity.

Total Runtime

Runtime is often directly linked to the fuel tank capacity, but this is not the only contributing factor.

Runtime is usually calculated based on half loads, which may seem a little odd at first. The tank and the motor both influence how long the generator is able to run.

Of course, the total run time will also be influenced by the number of appliances that you are trying to operate at once, and the number of watts that they eat up.

If you want to have your device last for longer, then you will need to be more cautious about the number of appliances you are trying to power up.


It is essential that you consider the number of outlets that the generator has, as this will influence the kind and amount of appliances that you can run without using things like adapters.

You may find generators with around two 120V outlets, or you can find at many as six. You are also going to need a device that has a 120V/240V 30A twist lock outlet if you are going to use the generator to power up heavy tools.

It’s also worth getting a 12V DC outlet as this can help you to charge batteries for RVs, boats or cars. A USB socket is also incredibly handy, but not all devices have them.

Amount of Noise

Generators have to work hard to power your electronics, so it makes sense that some of them can get pretty noisy.

It’s only natural that a generator is going to make some degree of noise, but how much are you willing to deal with? 

There are a lot of great generators on the market today that are pretty quiet. You can get some that make as little as 58db of noise, whereas others may make as much as 80db of noise.

Avoid a loud generator if you’re going camping or RVing and you don’t want to irritate the people around you.


Carrying a 200 lbs generator isn’t fun for anyone, so it’s worth thinking about how portable your generator is going to be.

There are many generators today that are designed for things like camping, and so they are fairly lightweight, or they have things that make them easier to move around such as telescoping handlebars and wheels.

On the other hand, if you are using your generator as a backup power option, then portability may not be a pressing concern for you.


When you’re buying a product, the chances are that the last thing you’re thinking about is that product breaking.

A generator can sometimes cost a substantial amount of money, and you don’t want to make an investment like that without protecting yourself in case anything goes wrong.

If you look for a manufacturer’s warranty it means that should anything go wrong, then the manufacturer can give you a refund or fix any issues within the warranty period.

Some warranties can last as little as one year, or they can span a 3 year time period. It often depends on the manufacturer.

Converter or Inverter Generators

When choosing a device, you can select between conventional generators or inverter generators. An inverter generator is fairly small and is designed to be portable. These generators will give you stable power, and they usually operate quite quietly.

On the other hand conventional generators are fairly large. They usually have a handle kit and wheels so you can more them more easily. They have much higher power than inverter generators, and they usually make more noise. 

Frequently Asked Questions

How do I ensure that I am safe when setting up my generator? 

For starters, you should make sure that you don’t try to get the generator to run inside your home or in any location that’s closed in. You also need to ensure that you don’t backfeed the electricity into the electrical grid of the home. Your appliances should be plugged right into the generator.

Before you top up the fuel reservoir, make sure that the generator has cooled down first. You should also ensure that you have any gear on hand to refill the generator, just in case the emergency situation you find yourself in lasts longer than expected.

It is very important that you ensure the generator doesn’t run out of fuel in case it damages the engine in the long run, and make sure you don’t leave any fuel inside the generator after you’ve finished using it, as this is another thing that can harm the engine in the long run.

Can you run any power sensitive electronics using a standard generator?

If you are running particularly power sensitive electronics, then you should opt for an inverter generator. This will give you the most stable power flow. 

Of course, it is possible to use a standard generator safely, but it can be a little risky.

If you want to run sensitive electronics with a standard generator, then you should check if the generator has a surge protector feature.

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    I'm an environment and energy blogger who teaches outdoor and energy enthusiasts how to be better informed when it comes to purchasing or maintaining a generator, solar panel system, or anything else related to your energy needs.