Best portable generator for home backup: picks by what you need to run

The "best" home backup generator is the smallest one that runs what you can't do without. Buy too small and the well pump won't start. Buy too big and you're feeding a 13,000 W engine to keep a fridge cold.

So this guide picks by job. Every model here lists a carbon monoxide (CO) shut-off on the maker's own page. We don't list gas generators without one. The figures come from makers' spec pages, linked at the end. We don't test units ourselves.

Quick picks

• Best fit for most homes: Westinghouse WGen7500DFc. 7,500 running and 9,500 peak watts on gas, dual fuel, a 120/240 V L14-30R outlet for a transfer switch or interlock. Runs the essentials plus a well pump, a window AC, or a 2 to 3 ton central AC.
• For a bigger house or more running at once: Westinghouse WGen9500DFc. 9,500 running and 12,500 peak watts on gas. It adds a 50 amp 14-50R outlet, so you're not capped at the L14-30's 7,200 W.
• The most watts here: DuroMax XP13000EH. 10,500 running and 13,000 peak watts on gas, 10,000 on propane, and the biggest tank (8.3 gal).
• Essentials only, quieter and lighter: Westinghouse iGen4000DFc. An inverter: 3,300 running and 4,000 peak watts, 62.8 lb. 120 V only, so no well pump or house hookup through a 240 V inlet.

Not sure what you need? Run the generator size calculator with your own appliances.

Side by side

Model	Running / peak W (gas)	Running W on propane	240 V outlets	Tank and run time (maker)
Westinghouse iGen4000DFc	3,300 / 4,000	2,970	None	1.69 gal; 7 h at 25%
Westinghouse WGen7500DFc	7,500 / 9,500	6,750	L14-30R	6.6 gal; 11 h at 25%
Westinghouse WGen9500DFc	9,500 / 12,500	8,500	L14-30R, 14-50R	6.6 gal; 12 h at 25%, 8 h at 50%
DuroMax XP13000EH	10,500 / 13,000	10,000	L14-30R, 14-50R	8.3 gal; 17 h at 25%, 8 h at 50%

All four are dual fuel and list a CO shut-off. None claims CARB compliance on the pages we used, which matters if you live in California. See CARB-compliant generators.

Step 1: what do you need to run?

Size by appliances, not by square feet. From our whole-house sizing guide:

What you'll run	About this many running watts	Pick
Fridge, sump pump, furnace fan, lights, Wi-Fi, TV	3,000 (4,400 to start)	iGen4000DFc or bigger
Those plus a well pump or a window AC	4,000 to 6,000	WGen7500DFc
Those plus a 2 to 3 ton central AC	about 5,000 to 6,000, with 240 V	WGen7500DFc
Central air plus a well pump, or a bigger AC	7,500 to 10,000, with 240 V	WGen9500DFc or XP13000EH

Starting watts matter as much as running watts. A well pump, sump pump or AC compressor needs a burst of often 2 to 3 times its running watts for a few seconds to start. Add only the single biggest starting surge to your total. Start big motors one at a time.

Step 2: do you need 240 volts?

Many homes need 240 V for a deep well pump, central air, an electric water heater or a dryer. A 240 V outlet is also how you connect a portable generator to the house through a transfer switch or interlock kit.

• L14-30R: 30 amps at 120/240 V. That's a ceiling of 7,200 W (30 × 240), whatever size the generator is.
• 14-50R: 50 amps at 120/240 V, up to 12,000 W.

This is why the bigger picks matter for big loads. A 9,500 W generator feeding the house through an L14-30 cord can only deliver 7,200 W of it. To use more, the WGen9500DFc and XP13000EH have a 14-50R, and your inlet and transfer switch must be rated 50 amps. See 30 vs 50 amp generator cords.

The iGen4000DFc has no 240 V outlet. It's for running a few things on extension cords, not for feeding the panel.

Step 3: connect it the safe way

There are two safe ways to power your home's circuits from a portable generator: a transfer switch or an interlock kit. Either one must be installed by a licensed electrician, usually with a permit. Consumer Reports calls a transfer switch "infinitely more convenient than an extension cord".

Never plug a generator into a wall outlet (a "suicide cord"). It can send power back into the grid and injure or kill utility workers, and it can start a fire. See interlock vs transfer switch.

Gas or propane for a long outage

All four picks run on gasoline or propane. Propane gives a little less power (the WGen7500DFc drops from 7,500 to 6,750 running watts) but stores far better. Gasoline goes stale: WEN's manuals, for example, say to use gas within 30 days. Propane in a sealed tank doesn't go stale.

Run times, from the makers:

• WGen7500DFc: 11 hours at 25% load on 6.6 gallons of gas, or 8 hours at 25% on a 20 lb propane tank.
• WGen9500DFc: 8 hours at 50% load on gas, or 7 hours at 50% on a 20 lb tank.
• XP13000EH: 8 hours at 50% load on 8.3 gallons of gas. DuroMax lists a 40 lb tank as the minimum for propane.

For a multi-day outage, plan on several 20 lb tanks, or gas cans with stabilizer, and rotate them. Our propane tank runtime guide has the math.

Carbon monoxide: the deal-breaker

The CPSC warns about generator carbon monoxide deaths ahead of every storm season, and its advice is blunt: never run a generator inside a home, garage, basement, crawlspace or shed, even with doors and windows open. Run it outside, far from the house, with the exhaust pointed away from windows, doors and vents.

A CO shut-off stops the engine when CO builds up around it. Consumer Reports says it only recommends portable generators with one, and suggests looking for an "ANSI/UL 2201" or "ANSI/PGMA G300" certification mark on the box. Every pick here lists a CO shut-off. Still, put battery CO alarms on every level of your home. Read our generator carbon monoxide guide and how far a generator should be from the house.

What about a battery instead?

A big power station makes no fumes and no noise, so it can sit indoors. The EcoFlow DELTA Pro 3 lists 4,096 Wh, 4,000 W and a 120/240 V L14-30R outlet, so an electrician can connect it like a generator. But 4 kWh keeps a fridge, lights and Wi-Fi going for about a day or two, not a week, and it can't run central air for long. Many homes pair a battery for nights with a generator for long outages. See power station vs generator and check the DELTA Pro 3 on Amazon.

Which one should you buy?

• Fridge, lights, Wi-Fi and a sump pump, run on extension cords: Westinghouse iGen4000DFc.
• Most homes, with a well pump, window AC or 2 to 3 ton central AC, through a transfer switch: Westinghouse WGen7500DFc.
• A bigger house, or central air plus a well pump: Westinghouse WGen9500DFc.
• The most running watts on propane, and you can handle a 40 lb tank: DuroMax XP13000EH.

Check the WGen7500DFc on Amazon · Check the WGen9500DFc on Amazon · Check the XP13000EH on Amazon · Check the iGen4000DFc on Amazon

FAQ

What size portable generator do I need for a power outage?

For the basics (fridge, sump pump, furnace fan, lights), about 3,000 running and 4,400 starting watts. Add a well pump or window AC and it's 4,000 to 6,000 running watts. With central air, plan on a 7,500 to 10,000 W generator with 240 V. Use the size calculator for your home.

Can a portable generator run a whole house?

It can run most of a typical house, but not everything at once. Run the essentials, start big motors one at a time, and skip heat-making loads like an electric dryer or oven while the AC runs. See can a 7,500 watt generator run a house.

Is a 7,500 watt generator enough for central air?

For a 2 to 3 ton central AC plus the essentials, usually yes, with a 240 V hookup. Start the AC with nothing else big running, and consider a soft start. Through an L14-30 outlet it can send at most 7,200 W to the house. See can a 7,500 watt generator run a house and generators for central air.

Do I need a transfer switch?

To power your home's circuits, yes: a transfer switch or an interlock kit, installed by a licensed electrician. Without one, you can only run appliances plugged into the generator with outdoor-rated extension cords.

Is dual fuel worth it for home backup?

For most people, yes. Propane doesn't go stale in a sealed tank, so you have fuel ready when a storm hits. You give up about 10% of the power. See dual fuel vs gas.