Portable Generators: Power Source and Size Guide

Before you compare brands or prices, settle one question: what will feed the generator, and what will you plug into it? Fuel type is the power-source decision, and it quietly shapes everything that follows, from where you store the unit to what you keep on hand before a storm. That spread is wide enough that a clear plan matters more than any single feature.

The second decision is wattage, and it comes in two numbers. Running watts is the power a generator can supply continuously. Starting watts, sometimes called surge, is a short burst available when a motor-driven appliance such as a refrigerator, pump or air conditioner kicks on. Motors often draw several times their running load for a moment, so a generator that covers your running total can still struggle at startup. Add up what you want to power at the same time, then check the listing for both figures. Some listings state only one number, which is worth noticing before you buy.

The third decision is inverter versus open frame. In general terms, an inverter generator produces power through electronic conversion, which is often chosen where cleaner electricity matters for sensitive electronics, while a traditional open-frame unit is the simpler, usually larger design. Neither word tells you how a specific model performs, so read the listing for what it actually states. Of the 144 listed models, three are described as cordless and the rest are fuel-driven, so most shoppers will be choosing among fuels, not batteries. Two picks below sit at opposite ends of the size range.

How to choose

Fuel type

Decide this first, because it determines storage, refueling and what you stock ahead of an outage. Gasoline is common among the models in this catalog, but listings differ, so check the title and description for the fuel the unit runs on. If you want a different fuel, filter for it before comparing anything else.

Running and starting watts

Running watts covers steady loads; starting watts covers the brief surge when motors start. List everything you want powered at once, total the running figures, then allow headroom for the largest motor starting. If a listing shows only one wattage figure, confirm what it refers to before treating it as your capacity.

Inverter or open frame

An inverter design is generally associated with cleaner output for sensitive electronics and is often smaller, while open-frame units are the more basic layout. Use the product title to see which design a model claims. A listing that mentions low THD is pointing at output quality, but the figure itself must appear in the listing.

Weight and portability

A generator for an RV or camping trip needs to be carried and loaded, while a job-site or home-backup unit may stay put. Missing weight is a reason to look closer.

Safety features and outlets

Some listings mention a carbon monoxide alert or sensor, and some mention a 50A outlet for larger connections. These are listed features, not promises about results. Match the outlets to the plugs you actually use, and treat any CO feature as an addition to running a generator outdoors, never a substitute.

What is in the box

A kit means a bundle, but the listing must say what it contains. Do not assume fuel, oil, wheels or cords are included unless the listing says so.

Our picks from the catalog

These picks come from what the listings state: prices, specifications and kit contents. Each says which listed facts it is based on.

Best budget pick

Pulsar 1600-Watt Recoil Start Gasoline Powered Inverter Generator with CO Alert

$299 to $450 · Size / capacity: 1600 W · Weight: 24 lb

This is the Best budget pick because it has the lowest price among the 127 models whose listings state at least one specification, listed at $299 to $450. The listing states 1600 W and a weight of 24 lb, and the title describes a recoil-start gasoline inverter with a CO alert. The 1600 W figure also suits only small loads.

See configurations and prices →

Best for heavy use

Westinghouse 28,000/20,000-Watt Remote Electric Start Gas Powered Portable Generator with Low THD, 50A Outlet, and CO Sensor

$3,799 to $3,899 · Size / capacity: 28,000 W

This is the Best for heavy use pick because it has the highest listed watts in its group, 28,000 W, and is priced at $3,799 to $3,899. The title describes remote electric start, a gas-powered portable design, low THD, a 50A outlet and a CO sensor, with 20,000 watts also named.

See configurations and prices →

Skip it if...

• Skip the budget pick if you plan to run several appliances at once, since its listing states only 1600 W.
• Skip the 28,000 W model if you only need to charge phones and run a few lights, because you would be paying $3,799 or more for capacity you may never use.
• Skip any listing that does not state both running and starting watts if you need to power motor-driven equipment, until you have confirmed the missing figure.
• Skip a cordless option if you need long, heavy-duty backup, since only three of the 144 listed models are described as cordless.

Buying checklist

• Choose your fuel before anything else.
• List every appliance you want to run at once.
• Total the running watts, then add headroom for starting watts.
• Decide between inverter and open-frame design.
• Check that the outlets match your plugs.
• Look for stated weight if you must carry the unit.
• Read the listing for what is in the box.
• Note any CO alert or sensor, and still run the unit outdoors.