Keep Your Tech Running In Your Car With These Expert-Recommended Power Inverters

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If you’ve been new-car shopping recently or even in the past few years, chances are you’ve noticed a few traditional 120-volt wall plugs in the dashboards, back seats, and truck beds of vehicles. These plugs rely on a device called an “inverter” to create household alternating-current power from the direct-current power supplied throughout the vehicle. These devices have some limitations, which we’ll discuss in a minute, but they can significantly increase the utility of your vehicle.

Car power inverters are available in a variety of shapes, sizes, and capabilities to let you plug an AC device into your car, SUV, truck, or RV. Don’t feel like buying a new car just to plug in your laptop? Then we’ve got you covered.

The simplest power inverters plug into your car’s cigarette-lighter or power-point to instantly provide a modest amount of plug-in capability, but it’s also possible to install larger, more powerful devices that can run space heaters, power tools, and other more serious equipment.

I’ve rounded up some of the best power inverters below. One of them will likely meet your needs. We’ll also discuss some situations where a power inverter is best avoided. Ready to plug in? Let’s get started.

Best Car Power Inverters

• Best Overall: Bestek 500 Watt

• Convenient Design: Bestek 200 Watt Power Inverter

• Best Budget Plug-In Inverter: Jupiter 120 Watt Continuous

• Best Budget Wired Inverter—Secure Mounting: Ommfarl 2000W

• Best Budget Pure Sine Wave: Renogy 2000W Pure Sine

The Expert: I’ve been using power inverters and mobile power for more than two decades, learning a few expensive lessons along the way. As a traveling racer in SCCA’s Prototype classes, I frequently find myself plugging in everything from a drill to a bench grinder on the road. So far, I've only had one major fire—from a low-quality inverter in 1999. My goal is for you to have none.

What to Look For in a Car Power Inverter

How much power do you need?

This can be tough to get your head around at first. Isn’t it just as simple as plugging something in and having it work? Not quite. Your car is very different from your house. To begin with, the supply of available electricity is limited by what the car’s recharging system and battery can provide.

Anything that dims the house lights briefly when you switch it on—like, say, a stage-sized amplifier for a bass guitar—is unlikely to work at all. Compact cars will have less power than many SUVs, which in turn will have less power than pickup trucks, which will have less power than RVs or commercial vehicles.

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The supply of available electricity is also limited by the inverter’s capacity, which is stated in watts. In general, you’ll want a safety margin of at least 20 percent over what your chosen item draws. How do you find that out? It’s often shown right on the device, but if it’s not there, it is almost always in the documentation or owner’s manual.

A cellphone charger might be just 5- to 20-watts, a laptop could be between 50- and 150-watts… but what about your hair dryer? Some of them can draw 2,000 watts. Nope, that’s not a typo; a hair dryer can require the power of 40 laptop computers. So make sure you know what you’re going to use with your inverter and plan accordingly.

Size, space, installation, and wiring

As a rule, more power means a larger inverter. Make sure the one you have in mind will fit. Just as important: there needs to be airflow around the inverter. This process generates heat, and the more power you draw the more heat the inverter will generate. Don’t put it next to flammable materials or wrap it up in something.

While most small inverters can be powered from a lighter plug, the heavier-duty items often require a direct connection to your vehicle battery. Not all inverters that require a battery connection come with the appropriate heavy-duty wiring, which must be purchased separately. Many of these large inverters are designed to be mounted in the vehicle with four or more screws, so be conscious of that as well.

Pure sine or modified sine—what does THAT mean?

Your car or truck probably runs on DC (direct current) power, which is simple: power flows from the positive terminal on the battery to the negative one. Your house uses AC power, which is less simple: power actually flows back and forth in a smooth wave. That’s why it’s called alternating current.

The primary job of an inverter is to take DC power and modulate it to imitate the AC power of your home. Most inverters are “modified sine,” meaning their alternating power is “choppy” instead of smooth.

Pure sine inverters use additional (and expensive) circuitry to better replicate what you get from the wall plug at home. The power they produce is smoother and less distorted, which can reduce the possibility of damage with some electric devices. They are more likely to carry the coveted UL rating for safety and quality. When in doubt, get pure sine—but understand this has a penalty in cost and size.

How We Selected Car Power Inverters

In addition to purchasing and testing inverters for my own use, I evaluated consumer feedback across hundreds of reviews, focusing on safety and reliability. I used these inverters in a variety of situations including outdoors, heavy load, and harsh physical treatment. These are the best car power inverters you can buy now.

500W Power Inverter

This is a remarkable bit of engineering at a reasonable price. It offers the option of lighter-plug or direct wiring, using alligator clips to the battery. You get 500 watts provided across two plugs—enough to handle the majority of portable-device needs.

There are two USB slots, which will draw less from the vehicle than plugging a phone charger into one of the AC plugs. It detects low voltage and will shut off. There’s a cooling fan to permit more installation options, and externally mounted fuses.

200 Watt Power Inverter

For a few dollars less than our Best Overall pick, this Bestek model gives you extra power wrapped up in a convenient package. The cylindrical shape is made to fit right into a car cupholder while the included cable plugs into the 12-volt source. Flip open the lid, and you’ll see two outlets, two USBs, and an extra 12-volt pass-through.

The 200-watt capacity is enough to run larger electronics, or perhaps a mini beverage cooler. Other features include a clickable power button, an internal cooling fan, and a 25-amp fuse that will sacrifice itself in the case of excessive power draw. The only drawback that I see with this design is that it may get in the way of actual drinks.

120 Watt Continuous

Let’s call this one the Laptop Warrior’s Choice because it has exactly what the average remote or mobile worker needs. For starters, there are 120 watts to power virtually any laptop, and two USB outlets for phones. There’s an LCD readout to let you know what’s happening, not to mention it’s compact and quiet.

No, you won’t be able to blow up an air mattress or dry your hair with this power inverter, but if you need to sit in a parking lot and finish your novel, this will be just the ticket.

2000W

Road tripping? Camping? This power inverter delivers 2000 watts. If you need that type of power, this is one of the most affordable ways to get it.

With thermal protection, an external status display, and a quiet fan, this device should be good to power larger items for a long time. It ships with sturdy cables for battery attachment and ground. It’s modified sine, so it’s not the best choice for sensitive equipment, but most campsite items should work well.

2000W Pure Sine

If you can deal with the additional space, price, and cooling demands, I strongly recommend the use of a pure sine wave inverter at this power level.

In addition to the greater safety of pure sine power, the Renogy offers thermal protection, a wired remote, and the ability to run sensitive devices like microwaves and refrigerators.

375W

You can get better specs elsewhere, particularly with regards to available USB power, but if you want the most durable inverter out there, Tripp-Lite is a solid bet.

This unit is compact and features a tough aluminum case. The power switch is easy to find and use. It’s supplied with direct wiring in addition to the cigarette plug, and it features a low-voltage shut-off.

3000W Pure Sine with Solar Inverter Capability

This isn’t a case of deja vu; Renology’s 2000W, elsewhere in this article, is our choice for Best Budget Pure Sine, and this is just a larger version of it. But Renology has a few tricks up its sleeve to make this a remarkable choice for RV usage besides the robust 3000-watt capability that can run two standard power tools at once.

It’s possible to expand the Renology to use solar power and invert that as well. Solar power, like battery power, is plain DC and requires an inverter to be useful. Renology allows you to hook its 100-watt panels in series to the inverter, so you can reduce your load on the RV’s engine and battery. In some circumstances, you can disconnect it entirely. This can be a literal lifesaver, and we’re all about it.

3000 Watt Pure Sine

If you’re serious about powering high-draw devices, Harbor Freight’s flagship inverter is calling your name. The competition offers three or even four AC outlets, but this one has just two—with GFCI protection, just like your local building code probably requires.

The Jupiter clearly displays both the available power output and input level, which allows you to immediately diagnose problems with equipment that won’t start. It can boost to 6000w for short periods of time to help start a saw or other power tools.

There is a simple and mountable wired remote. Cables are not included. If you want to get heavier duty than this, you will probably need to contact an industrial supplier. This is a stout piece of equipment.

300W Pure Sine

Compared to the Jupiter plug-in 120-watt inverter that I’ve also selected as one of our top nine products, this is a larger and heavier device. But there’s a benefit: 300 watts of pure sine power, plus smart USB ports.

If your laptop isn’t happy charging on a modified sine wave, or if you like the idea of plugging in a travel cooler, this option works. A pair of smart USB ports will also ensure faster charging to tablets and other devices that require elevated levels of USB power for sustained periods of time.

Let me share just one caveat: at 300 watts, the draw on your car battery will be considerable, so don’t use it for long periods of time without running the engine.

Our Expert Jack Baruth is Plugged In on Power Inverters. Check Out His Tips Here.

Will a power inverter drain my car battery?

If your car isn’t running—yes, absolutely! And the more power you demand, the faster that will happen. A laptop can often run for a few hours off a car battery and inverter without impairing the vehicle’s ability to start. A box fan, impact drill, or hair dryer can drain a battery in minutes. Some inverters will detect a low-voltage condition and shut down, but that’s not something on which you should rely.

If your car is turned on and running, it’s still possible to pull more power than your vehicle is generating to recharge the battery. Make sure your alternator and battery are in top condition. If your vehicle shows battery voltage, keep an eye on that. When in doubt, take a break and let the vehicle charge.

What can’t I use in a power inverter?

In theory, any household appliance should run perfectly in a high-quality pure sine inverter. In practice, running a PA system, table saw, or welder is going to pose a challenge.

With the more affordable modified-sine inverters, it is generally accepted that devices with large traditional AC motors—think refrigerator, pumps, and saws, for example—may be damaged in the long term. Some laser printers, 3-D printers, and other specialty electronic equipment may be damaged by, or may fail to operate with, a modified sine inverter. When in doubt, ask the manufacturer.

How long will one of these last?

If you keep it cool, use it below its maximum rating, and protect it from vibration or impact damage, your inverter may last a long time. Run it hot or load it to the max, it won’t last as long.

Inverters are sensitive to vibrations or being dropped, so don’t expect that you’ll get a lifetime’s worth of use from the inverter in the saddlebag of your Harley or adventure bike.

Is it possible to blow a power inverter’s fuse? What then?

It is absolutely possible to blow a fuse or trip the breaker in your inverter. When that happens, don’t start using it again until you completely understand what happened to cause the blow or trip in the first place. Then take steps to prevent that happening again. If you just reset or replace and go back to the same use, don’t be surprised if it happens again, or if you wind up having to put out a fire.

Do I really need a power inverter, or do I just need a good DC charger?

You’d be surprised how many people plug a power inverter into their cigarette-lighter outlet, then plug an AC cellphone charger into the inverter. Don’t do that. You’re wasting power and increasing the load on the car.

It’s possible nowadays to charge any large phone or tablet, and even some laptops, with the new generation of USB-C power-point chargers. Take a look at them and see if they’ll satisfy your requirements.

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