Photo illustration of a Honda inverter generator

Portable gas generators have had several key technological makeovers recently. One is critical to safety, and one significantly boosts the level of performance for a certain breed known as inverter generators. 

To reduce the risk of carbon monoxide poisoning, some new portable generators feature a built-in sensor that triggers an automatic shutoff if CO builds up to dangerous levels in an enclosed space. And some also have engines that emit less CO in the first place.

Recent CR test data show that these safety features are likely to save lives. Based on this finding, CR can no longer recommend any portable generator that doesn't pass our new CO safety technology test. (The test doesn't apply to home standby models.)

More on Generators

If you’re looking into getting a portable generator, you may want to consider an inverter generator when the new models with a CO safety shutoff begin appearing online and on retailer shelves. As a type, inverter generators are more expensive than conventional portable models, but they have distinct advantages.

An inverter generator electronically throttles the engine up and down to meet demand instead of running full tilt all the time. The resulting improvement in efficiency means that you won’t have to fill up the gas tank as often. Inverter generators also produce lower emissions and are generally very quiet.

“You can carry on a conversation next to an inverter generator,” says Dave Trezza, who oversees CR’s generator testing.

A New Class of Generator

To help you make better sense of your options, we break our inverter generator ratings into three groups:

1. Large
With very few exceptions, the large inverter generators in our ratings weigh around 250 pounds or more (wheels included). That’s too big to haul along to a tailgate party and just big enough to power your house. They generate 5,000 watts of power or more (at 220 volts).

This category of inverter generator can be connected directly to your electrical panel with a safety device called a transfer switch, which CR strongly recommends.

2. Midsized
These weigh 80 pounds or more and might come with wheels. They produce 2,500 to 4,500 watts but don’t allow the recommended option of connecting to your electrical panel with a transfer switch. Instead, you plug appliances or electronics directly into the generator, which can be dangerous if you don’t follow certain guidelines.

This size is well-suited for users of recreational vehicles. They’ll produce all the power you need for plug-in appliances like a toaster or microwave, and they’re light enough to unload and carry away to a safe distance from your RV before use.

3. Recreational
These weigh 50 to 60 pounds and are designed to be carried with one hand. Most recreational models max out at around 2,000 watts, which should be plenty for tailgating or camping.

"Don’t let the size lull you into a false sense of security," says Trezza. "Even though they're about as big as a gym bag, our tests show that these models emit carbon monoxide at a rate that can quickly build up to unsafe levels in an enclosed space."

How to Run a Generator Safely

Consumer Reports has tested more than a dozen inverter generators. None in this current batch have the automatic CO shutoff, and so none are CR recommended.

They range in capability from the compact type you’d want for tailgating or camping to something that could be a steady source of basic backup power after a storm. Our buying guide is a great place to get a lay of the land, and our ratings will let you compare specific models.

CR members can read on for ratings and reviews of three top-performing inverter generators (one each from the three sizes we test).

3 Top Inverter Generators From CR's Tests

Top Picks


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Power delivery
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