Adam holds a Bachelor's and a Master's degree in Linguistics, and creative writing has always been his greatest passion. For more than 25 years he's been working for several well-known automobile and travel magazines as an editor and expert consultant, but when Adam started his writing path here, at WisePick, it turned out that he's capable of writing practically anything about everything.
Initially being an engineering specialist, Tom has never stopped learning and acquiring other knowledge and skills. Now he’s involved in technical support for a well-known household appliances manufacturer, so no wonder he knows everything about almost everything you buy for your home.
Last updated: June 28, 2021
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Having a generator can make a huge difference when the power goes out or when you’re headed into the great outdoors on a road or camping trip. The best 4000-watt generator offers enough power to keep your essential appliances – like your refrigerator, freezer, water pumps, and lights – running during a power outage without being overly large, heavy, or gas-guzzling. At the same time, 4,000 watts is the perfect amount for powering a medium-sized RV or even electrifying a campsite.
In order to find the best 4000-watt generators on the market today, we considered a number of features. First, we checked whether the 4000-watt rating describes the continuous power, the maximum wattage the generator can produce steadily, or the surge power, which the generator can only hold for a few seconds while motorized appliances start up. We also considered the runtime that each generator offers given its fuel tank size and efficiency. The amount of noise generators produce was an especially important consideration when looking at the best 4000-watt generators for RVs and camping. Finally, we considered how the warranties on different generators stacked up.
We spent tens of hours researching the most well-liked 4000-watt generators, poring over technical specifications and reading through customer reviews. The result is our pick of the seven best 4000-watt generators, highlighted in the table below. Continue reading for detailed reviews of each generator, complete with pros and cons. Our buying guide covers everything you need to know about choosing the generator that is right for your needs. Finally, we sum up our three overall favorite 4000-watt generators.
This powerhouse generator from Westinghouse is extremely well-equipped for any use, although expect to pay a premium for the wide array of included features. The generator offers 3700 watts of continuous power and 4500 watts of surge power, a differential wide enough to allow you to safely start motor-driven appliances without unplugging everything else from the generator. The four-stroke engine allows this generator to be highly fuel efficient – the unit boasts a massive 18-hour runtime while sucking up just 3.4 gallons of gasoline.
Users were blown away by how quiet this generator is. At just 52 dB, it is not only the quietest generator we reviewed, but also more than 10 dB quieter than the average for generators in this size class. The generator has both electric and recoil start options, which users appreciated so that there is a backup in case the generator’s battery is exhausted.
The face of the generator has two 120V household outlets, a 30A outlet, a 12V DC outlet, and two USB ports for charging small electronics. However, there is not an RV-ready outlet, which is the biggest drawback to this generator. Users were very happy with the LED display, which makes it possible to see how many watts are being drawn from the unit and how much runtime is left based on fuel consumption.
Westinghouse offers a three-year warranty on this generator for residential users, but commercial users should beware that they will receive only a one-year warranty.
This modestly priced generator from Champion is an all-around performer designed to work well at home for providing power during a power outage or for everyday use in your RV. The generator is rated for 3500 watts of continuous power output and 4000 watts of surge output, which means that you may have issues starting motor-driven appliances if running this generator close to its maximum power. That said, users were extremely happy with the clean electrical waveform put out by this generator, which allows it to be used safely for powering and charging sensitive electronics.
The generator only has two 120V household outlets, but RV users greatly appreciated the RV-ready twist-lock outlet and the 12V DC battery charging outlet in case of any issues with the RV’s battery. The generator is extremely fuel efficient at half-load, running for up to 17 hours while using less than three gallons of gas. However, users note that the generator can be somewhat noisy for evening or early morning use, especially at a campsite, at 64 dB. In addition, many users wished for an electrical start function, although they found that the recoil start was responsive and reliable.
The generator comes with a limited three-year warranty from Champion, although users reported no issues with the generator over that timeframe.
This compact generator from Pulsar features a slightly different construction compared to the other generators we reviewed, with a single carry bar across the top and integrated plastic wheels as opposed to a full metal frame. This, along with the telescoping handle, makes this one of the most portable 4000-watt generators available.
The generator has a 224cc engine but outputs only 4000 watts of surge power and 3500 watts of continuous power, so it is not ideal if you have a lot of motorized appliances to power. The fuel efficiency and runtime are middle of the road, using 3.4 gallons of gas to run the generator at half load for 15 hours. Although the noise level is not extreme at just 63 dB, some users felt that the generator made a lot of annoying whining noises when running near its rated wattage. Users did like the electric start, though, and were very happy with the ability to start the generator remotely with the included controller.
The outlet panel is relatively well-equipped, with an RV-ready twist-lock outlet and a USB port for charging small electronics. It also has a 12V DC outlet for charging batteries, which combined with its portability makes this generator a contender for use in an RV or during road trips. However, note that it only has two standard 120V outlets.
Pulsar offers a two-year warranty on this generator and users note that parts for this brand are carried by most hardware stores and repair shops.
This generator from Westinghouse features six 120V household outlets and two USB charging ports, making it an ideal choice for home use during a power outage when you need as many outlets as possible. However, note that it does not come with a 30A outlet, a 12V DC outlet, or an RV-ready outlet as found on most other generators, and thus is largely limited in its range of uses.
This generator is rated for 3500 watts of continuous power or 4200 watts of surge power, so it has plenty of juice to cover all of the essential appliances in your home in the event of a power outage. Even better, the generator is extremely fuel efficient at half load and takes just 2.6 gallons of gas to run for up to 15 hours. Users also appreciated how quiet this generator is, at between 52 and 59 dB depending on the power draw. This low noise level meant that it could be used overnight in some cases without waking up the house or the neighbors.
The generator does not have an electric start, one of the biggest requests from users. However, users did appreciate the LED panel that shows the wattage being drawn from the generator as well as the remaining runtime.
Westinghouse offers a three-year warranty on this generator for residential users but limits the warranty to just one year for commercial users.
This heavy-duty generator from Wen is perfect for household use if you need to push the envelope of what a generator in this size class can offer. The generator is rated for 3750 watts of continuous power, but boasts an impressive 4750 watts of surge power – the most of any 4000-watt generator we reviewed. That said, all this power comes at a cost: the generator has relatively poor fuel efficiency and can guzzle it’s entire four-gallon fuel tank in just 10 hours at half load.
Users greatly appreciated the electric start on this generator for how easy it makes it to start using the generator, even from cold. The face of the generator features a 120V RV-ready twist-lock outlet, although the frame of the generator can be good or bad for an RV depending on the size of your vehicle. On the one hand, the built-in wheels make the generator more portable for rolling around camp, but on the other hand, they increase the size and bulk of the unit. The generator also has only two standard 120V outlets and does not have a 12V DC outlet for charging a battery.
Although the generator is certified by the CARB and EPA for low emissions, users noted that it can be extremely loud compared to other generators of this size – it produces 68 dB of noise when operating, enough to cause complaints if you use it around a campsite at night. Wen offers a two-year warranty on this generator.
This XtremepowerUS gasoline generator is an impressive model. It has a 212cc engine that will be able to give you all of your needs. It’s very well designed to not only give you reliable power but also a high level of usability.
Despite the high level of power, the generator is surprisingly easy to move. It doesn’t weigh too much and has wide handles. For two people, it shouldn’t be too difficult to put it where you need it.
One of the biggest downsides to portable generators is that they can be unbearably loud. While all generators are going to make plenty of noise, this is one on the quieter side. At 67dB you don’t have to worry about drowning out all other sound and needing to shout over it.
It’s not the most powerful generator around, but it’s perfect for the likes of campsites, construction areas, tailgates and parties. A few users have reported some delivery issues, but this doesn’t seem to be a common issue.
The recoil start on this model is excellent and makes it very easy to get going. It requires minimal effort, especially compared to some other generators on the market. All of this comes at a very impressive price which makes it excellent value for money.
This inexpensive and compact generator from DuroStar is an ideal choice for those who need a generator on a budget or those who want a generator for a potential emergency but don’t want to spend a fortune on a tool they won’t use frequently. The four-stroke engine puts out a relatively weak 3300 watts of continuous power but is capable of producing up to 4000 watts of surge power. Even though four-stroke engines are usually more fuel efficient, this generator guzzles gasoline and can run through its entire four-gallon tank in just eight hours at half load.
The outlet panel is moderately equipped, with two 120V household outlets and a 30A twist-lock outlet for tools with a larger current demand. The panel also has an analog display that shows the wattage being used, although this can be somewhat difficult to read. Users warn that this generator can be quite loud as it is rated for 69 dB of noise. However, given the inexpensive price, most users were happy with the recoil start and were not surprised at the lack of an electric push start.
The warranty is also short on this generator at just one year, which is not surprising given the price. However, users found that it continued to work well over several years of intermittent use.
Now that you’ve learned more about our seven favorite 4000-watt generators on the market today, how do you choose between them to get the generator that is right for your needs? Choosing the right generator largely depends on how you plan to use it – which affects the features you need – and your budget. In this buying guide, we’ll cover the basics of what you can power with a 4000-watt generator and highlight the important features that you need to know about to make the best decision.
What can you power with a 4000-watt generator?
In order to figure out how much power you’ll be drawing from your 4000-watt generator, you need to add up the wattages of all the appliances you plan to plug into it. However, there’s a catch because any appliances that are driven by a motor – such as your refrigerator, freezer, and air conditioning unit – have two different wattage requirements: running wattage and surge wattage. Running wattage describes how many watts the appliance uses to keep running once it has already started. Surge wattage is typically higher, and is sometimes much higher, and describes the amount of wattage the appliance uses for the few seconds when the motor is starting up.
Thus, you need to make sure that the sum of all the running wattages of the appliances you want to power with your 4000-watt generator is less than 4000 watts, while the sum of all the surge wattages plus the running wattages of non-motorized appliances is less than the surge wattage that your generator is rated for.
To give an example of what a 4000-watt generator is capable of powering, let’s look at some of the common appliances found in a house or RV. 4000 watts give you enough power to run a refrigerator and freezer, microwave, and air conditioning unit, with just a few hundred watts left over for turning on lights and charging small electronics. However, beware that the surge wattage to run these appliances is closer to 5000 watts because they are driven by motors.
Important features to consider before you buy a 4000-watt generator
In order to choose the best 4000-watt generator for your needs, there are a variety of important features on generators that you need to understand because they affect how the generator will work under different circumstances. In this section, we’ll explain these features, what they mean, and how they can impact your purchasing decision.
Rated and maximum power output
All modern generators have two different power outputs – their rated power and their maximum output, or surge, power. The rated power describes the amount of wattage that the generator is able to consistently put out for as long as it has fuel and is the wattage that you cannot exceed once you have all your appliances up and running. For non-motorized appliances, like light bulbs, dishwashers, and even microwaves, the running wattage is the only wattage that matters and you can determine how much wattage your appliances will need simply by adding up all of their individual running wattages.
Note that all of the 4000-watt generators we reviewed actually have rated wattages under 4000 watts.
Maximum power output comes into play when you are powering motorized appliances like refrigerators, freezers, air conditioning units, and some types of pumps. When these appliances are first plugged into the generator, the motor requires a much larger power draw to start up than it does to run once it has started. The maximum power output on your generator will be able to handle this extra wattage requirement for a few seconds, long enough to start these appliances. If you have left yourself leeway when calculating your running power requirement, your generator will likely provide enough surge power to get all your appliances started as well.
The engine is the heart of your generator as it is the component of the generator that converts fuel – either gasoline or propane – into electrical energy. In general, a more powerful engine will produce more power, so that generators that offer roughly equivalent output wattages have similarly sized engines – this is why most of the 4000-watt generators we reviewed have 212cc or 224cc engines.
Fuel tank capacity
All of the 4000-watt generators we reviewed run solely on gasoline, which means that have an internal fuel tank to hold the gasoline. The fuel tank size on these generators does not vary by much and is typically 3.4 to 4 gallons. However, the Westinghouse iPro4200 has a small 2.6-gallon tank, which reduces the overall size of the generator but also reduces the runtime and requires you to refill the fuel tank more frequently. In general, a larger fuel tank will increase the runtime – although this also depends on fuel efficiency – and increase the size of the generator.
The runtime of a generator is typically measured at half-load (i.e. when the generator is running at half its rated wattage) and is a measurement of how long the generator can run on a single tank of fuel. The runtime depends on both the size of the fuel tank and the efficiency of the generator’s motor. Generator runtimes on 4000-watt units range from just eight hours at half load on the DuroStar generator to an impressive 18 hours at half load on the Westinghouse iGen4500.
Note that the generator’s fuel efficiency depends in large part on how much wattage is being drawn from it. For a single generator, the runtime will be shorter when running it at maximum capacity compared to running it with only a single appliance plugged in.
The number and type of outlets found on your generator are extremely important since it determines what types of appliances and how many appliances you can plug in without having to resort to power strips and electrical adapters. The number of standard 120V outlets can range from just two, like on the DuroStar and Pulsar generators, to as many as six on the Westinghouse iPro4200 generator. If you plan to use your generator to power heavy tools, it is important to look for a unit that offers a 120V/240V 30A twist-lock outlet. On the other hand, if you want to use your generator to power an RV, an RV-ready 120V outlet like the kind found on the Wen generators may be the most important outlet to have. In addition, some generators like the Westinghouse models and the Pulsar generator offer USB ports for charging small electronics. Another outlet that can be extremely useful is a 12V DC outlet, like that on the Champion generator, that can be used to charge a battery for your car, RV, or boat.
Although you may be focused in on power when looking at generators, it’s also important to consider how much noise a generator will make once it is started up. Noise is a particularly important concern if you plan to use your generator for an RV or camping. The noise of a loud generator can wake up an entire campsite or prevent you from falling asleep. Even for home use, a loud generator can keep you or your neighbors up at night and generate complaints.
In general, generators with larger engines will produce more noise, although the amount of noise reduction built in by the manufacturer can also play a large role in noise. For example, the Westinghouse generators produce only 52 dB of noise while the similarly powerful DuroStar and XtremepowerUS 4000-Watt Gasoline Generator generators produce 67-69 dB of noise.
Size, weight, and portability
The size, weight, and portability of different generator models can matter more or less depending on where you plan to keep it and how you plan to use it. For occasional household use where the generator sits in the same place where you expect to use it, portability may be a non-issue. On the other hand, if you plan to use your generator with an RV for camping, having an enormous and heavy generator can be problematic. Thankfully, although 4000-watt generators are heavy to carry by yourself, most are manageable in size compared to larger generators. If portability is a serious concern, the Wen, Pulsar, and Westinghouse iGen4500 generators are mounted on a set of wheels to make them easier to move around.
A 4000-watt generator is a significant investment so you want to be sure that your generator will work like new for many years to come. A manufacturer’s warranty can protect your purchase in case anything goes wrong with your generator and helps to provide peace of mind for your purchase. Warranties vary in length from just one year on the DuroStar unit to up to three years on all of the Westinghouse and Champion generators.
How much should you expect a 4000-watt generator to set you back? These units range widely in cost, but you should expect to pay at least several hundred dollars to get a reliable unit. Our budget pick, the DuroStar generator, costs just over $250, while the Pulsar and Westinghouse iGen4500 models run for $850 and $950, respectively.
When looking at generators, opt for the most reliable model that has the surge power and features you need – it’s better to pay a little extra now than have to buy a new generator in a few years.
Once you have your new generator in hand, how do you hook it up? Here are some of our favorite tips to help you get started with your generator.
For safety reasons, never operate the generator inside or in enclosed areas.
Plug appliances into the generator rather than trying to backfeed electricity directly into your home’s electrical grid – it’s illegal!
Always allow the generator to cool down completely before adding more fuel to the reservoir.
Keep enough motor oil and filters on hand – in addition to gasoline – to get you through an extended power outage.
Don’t allow the generator to fully run out of gas, as this can damage the engine.
Never leave gas in the generator after you’re done using it as it can go stale and cause engine damage the next time you start it up.
4000 watts of running power is enough to power a standard refrigerator and freezer, a microwave, and a small air conditioning unit, plus household or RV lights. If you have a set of appliances you intend to power with your generator, add up their running wattages to make sure they are under 4000 watts total, and keep an eye on appliances with surge wattages to ensure your generator can handle the startup load.
The noise that 4000-watt generators produces varies between models but is broadly between 50–70 dB. The quietest generators we reviewed, the Westinghouse iPro4200 and iGen4500, produce only 52 dB, while the louder generators we reviewed like the Sportsman and DuroStar generators produce 69 dB of noise.
Typically, not. Generators that allow you to switch between 110V and 220V only allow you to run one voltage at a time, although you can install a power converter on one of the outlets to turn 220V power into 110V power.
Our three overall favorite 4000-watt generators on the market today are the Westinghouse iGen4500, the Champion Power Equipment 100302, and the Pulsar PG4000iSR. All three of these generators are highly fuel efficient and offer extended runtimes of 15, 17, and 18 hours, respectively, while also producing relatively low levels of noise. The Pulsar and Champion generators both have RV-ready twist-lock outlets, making them a perfect choice for powering a road trip. The Champion generator also comes with a three-year warranty, one of the best warranties in its class. Meanwhile, the Pulsar and Westinghouse generators are mounted on wheels to make them more easily portable. We feel the Westinghouse generator is the overall best 4000-watt generator because of its massive 4500-watt surge power, its extremely quiet 52 dB engine, and the inclusion of an LED screen on the front panel to monitor wattage use and runtime.