Not sure what size you need?
Use the calculator to find your exact load, then come back to decide portable vs standby.
Open the Generator Size Calculator →Want a quiet, fuel-free option? Size a solar generator & power station instead.
What is the short answer?
If you need to power a few essentials during an outage and want the lowest cost, a portable generator is the right call. If you want automatic whole-home backup that turns on by itself and handles central AC, a standby generator is the practical choice. The decision comes down to how much of your home you need to power, how often outages hit, and your budget.
How do portable and standby compare side by side?
Portable generator
- Cost: $400 to $2,000
- Power: 2,000 to 12,000 watts
- Installation: None required; wheel it out and plug in
- Fuel: Gasoline or propane, refill as needed
- Startup: Manual, pull or electric start
- Best for: Essentials, occasional outages, budget buyers
Standby generator
- Cost: $3,000 to $6,000 plus installation
- Power: 10,000 to 25,000+ watts
- Installation: Professional, with a transfer switch
- Fuel: Natural gas or propane, automatic
- Startup: Automatic within seconds of an outage
- Best for: Whole-home coverage, frequent outages, central AC
What are the key differences that matter?
| Factor | Portable | Standby |
|---|---|---|
| Upfront cost | $400 to $2,000 | $3,000 to $6,000 + install |
| Total installed cost | ~$400 to $2,500 | $4,500 to $9,000+ |
| Power capacity | Up to ~12,000W | 10,000W to 25,000W+ |
| Runs central AC? | Only small units, with care | Yes, sized to handle it |
| Starts automatically? | No, manual | Yes, within seconds |
| Fuel source | Gasoline / propane, you refill | Natural gas / propane, automatic |
| Installation | None (extension cords or transfer switch) | Professional + transfer switch |
| Noise | Louder, run when needed | Quieter, runs automatically |
| Maintenance | You manage it | Self-tests, less hands-on |
When does a portable generator make sense?
You only need to power a few essentials (fridge, lights, furnace fan, well pump, a window AC). Outages are occasional. You want the lowest cost and are fine starting it manually. A portable in the 5,000 to 7,500 watt range covers most essentials.
When does a standby generator make sense?
You want whole-home coverage that runs central AC and large appliances automatically. Outages are frequent or long. You are willing to invest in professional installation for the convenience and peace of mind. A standby in the 12,000 to 25,000 watt range handles a typical home.
Which models are typical in each class?
Two examples per class, one at the value end and one at the premium end. Sizing comes first: match the generator to your calculated load, then compare models within that bracket.
| Class | Value pick | Step-up pick |
|---|---|---|
| Portable Essentials, occasional outages |
Westinghouse 4650 Peak Watt | DuroMax XP13000HX Dual Fuel |
| Standby Whole home, automatic, installed |
Generac 14kW Whole Home | Larger standby units are typically quote-only from a local installer, not sold online. |
As an Amazon Associate I earn from qualifying purchases. These are examples of each class, not tested recommendations, and standby installation cost is not included. Verify rated running watts against the nameplate before buying.
Our honest take
Most homeowners start with a portable and add a standby only if they find themselves hauling it out every month. If you are testing whether backup power matters to you, a portable is the low-risk first step. If you already know you need whole-home backup and can afford the install, a standby is the better long-term buy. There is no wrong answer, only the one that matches your needs and budget.
Which guides answer the next question?
If you already know the class you want, size the load first:
- What size generator for a well pump? (1/2 HP and 1 HP, plus the 240 volt catch)
- What size generator for a sump pump? (1/2 HP and 1 HP, and why storms are worst)
- What size generator for a refrigerator and freezer? (startup watts plus food safety time)
- What will a 7,500 watt generator run? (a full worked example)
- Generator wattage chart (running and starting watts)
Find your exact size
Use the calculator to see whether your load fits a portable or needs a standby.
Open the Generator Size Calculator →Want a quiet, fuel-free option? Size a solar generator & power station instead.
Disclaimer: Cost and power figures are typical ranges for planning purposes only and vary by brand, model, and local installation rates. Always consult a licensed electrician before installing or connecting a generator. Never run a generator indoors.