Generator sizing
Generator Wattage Chart 2026: Running + Starting Watts for 50+ Appliances (NEC 702)
Wattage chart + calculator Based on NEC 702 (NFPA 70) & manufacturer specs Reviewed by the WhatSize editorial team
Based on NEC 702, DOE Energy Use Chart, manufacturer spec sheets (Generac, Honda, Champion)
Quick answer
Generator size = your appliances’ total running watts × 1.25 + the largest single starting surge. A typical 2,000 sq ft home needing fridge, sump pump, furnace blower, and lights requires a 5,000–7,500 watt generator. Use the chart below to add up your appliances, then use our free calculator to get an exact size in 60 seconds.
Appliance Wattage Chart: Running & Starting Watts
All figures are typical for modern US appliances. Starting watts (surge) are 2–7× running watts for motors; resistive loads (heaters, lights) have no surge.
| Appliance | Running W | Starting W | Notes |
|---|---|---|---|
| Refrigerators & Freezers | |||
| Refrigerator/freezer (20 cu ft) | 150–200 | 600–800 | Surge 3–4× running |
| Chest freezer (15 cu ft) | 100–150 | 500–700 | |
| Side-by-side fridge w/ ice maker | 200–250 | 800–1,200 | |
| Sump & Well Pumps | |||
| Sump pump 1/3 HP | 400–500 | 1,200 | |
| Sump pump 1/2 HP | 800–1,000 | 2,100 | |
| Sump pump 3/4 HP | 1,100–1,500 | 2,800 | |
| Well pump 1/2 HP | 1,000 | 2,000 | |
| Well pump 1 HP | 2,000 | 4,000 | |
| Heating & Cooling | |||
| Furnace blower 1/3 HP | 600–800 | 1,200–1,500 | |
| Central AC 2.5 ton | 3,500 | 7,000 | Surge 2× running |
| Central AC 3 ton | 3,500–4,000 | 7,000–8,000 | |
| Central AC 5 ton | 6,000 | 12,000 | |
| Window AC 6,000 BTU | 600–750 | 1,200–1,500 | |
| Window AC 10,000 BTU | 1,200–1,500 | 2,400–3,000 | |
| Major Appliances | |||
| Electric water heater (50 gal) | 4,500 | — | Resistive, no surge |
| Electric dryer | 5,400 | — | Resistive, no surge |
| Electric stove (per burner) | 1,500 | — | |
| Microwave oven | 1,000 | — | |
| Dishwasher | 1,200 | — | |
| Washing machine | 500 | 1,500 | |
| Electronics & Lighting | |||
| LED lights (10 bulbs) | 100 | — | |
| TV (50″ LED) | 100 | — | |
| Desktop computer + monitor | 200–400 | — | |
| WiFi router + modem | 10–20 | — | |
| CPAP / medical device | 60–150 | — | |
How to Calculate Generator Size: The NEC 702 Formula
Total Required Watts = (Σ Running Watts × 1.25) + Largest Single Starting Surge
1
Add up running watts of all appliances you want to power simultaneously.
2
Multiply by 1.25 — the NEC 210.20(A) continuous-load margin for circuits expected to run 3+ hours.
3
Add the largest single starting surge — only ONE motor starts at a time. NEC 702 doesn’t require summing all surges.
NEC 701 vs NEC 702: Which Applies to Your Generator?
You may see both “NEC 701” and “NEC 702” cited in generator sizing guides. Here’s the difference:
NEC Article 701
Legally Required Standby Systems. Applies to hospitals, fire pumps, elevators, sewage treatment — systems that must run by law during outages. Requires automatic transfer switch. Not applicable to typical residential generators.
NEC Article 702 — Residential Standard
Optional Standby Systems. This is the code that applies to your home generator. Covers portable and standby generators used voluntarily during outages. All wattage recommendations on this page follow Article 702.
Generator Size Guide: What Each Wattage Tier Can Run
| Generator Size | Can Run | Best For | Typical Price |
|---|---|---|---|
| 2,000–3,500W | Fridge, lights, phone charger, 1-2 small appliances | Camping, RV, short outages | $400–$800 |
| 5,000–7,500W | Fridge, sump pump, furnace blower, lights, window AC | Home essentials backup | $800–$1,500 |
| 10,000–15,000W | Most home circuits, well pump, central AC (with soft start) | Whole-home portable | $1,500–$3,000 |
| 20,000–26,000W | Entire home including central AC, electric appliances | Whole-home standby | $5,000–$12,000 installed |
Best Generators by Size: Our Top Picks
Each pick is verified to meet or exceed the NEC 702 wattage requirements. We sort by specs, not commission. Read our product policy.
Best Portable Generators
DuroMax XP10000E 10,000-Watt Gas Powered Portable Generator - Electric Start, Whole Home Backup Power, Transfer Switch Ready, RV & Emergency Ready #ad
★★★★☆ 4.6 · 666+ · $1560
Yamaha EF3000iSEB, 2800 Running Watts/3500 Starting Watts, Gas Powered Portable Inverter #ad
★★★★☆ 4.7 · 30 · $1550
YAMAHA EF3000iS, 2800 running Watts/3000 Starting Watts, Gas Powered Portable Inverter #ad
★★★★☆ 4.6 · 28 · $1995
WEN 56200i 2000-Watt Gas Powered Portable Inverter Generator, CARB Compliant,Black & Orange #ad
★★★★☆ 4.6 · 1K+ · $490
Generac 6864 XD5000E 5000-Watt Diesel-Powered Portable Generator - Ideal for Emergency Backup Power and Job Sites - Reliable Power for Demanding Applications - CARB Compliant #ad
★★★★☆ 4.6 · 25 · $4249
A-iPower SUA4500 4500 Watt Portable Generator Gas Powered Wheel Kit Included, EPA/CARB complied #ad
★★★★☆ 4.6 · 35 · $469
DuroMax XP12000EH 12,000-Watt Dual Fuel Portable Generator – Gas & Propane, Electric Start, Whole Home Backup Power, Transfer Switch Ready, RV & Emergency Ready #ad
★★★★☆ 4.6 · 3K+ · $1299
DuroMax XP5500EH 5,500-Watt Dual Fuel Portable Generator - Gas & Propane, Electric Start, RV & Emergency Ready #ad
★★★★ 4.2 · 2K+ · $748
Pulsar 10, 000W Dual Fuel Portable Generator with Switch & Go Technology & Electric Start, PG10000B16 Non-Carb Approved #ad
★★★★☆ 4.6 · 176+ · $1389
Westinghouse 2200 Peak Watt Super Quiet & Lightweight Portable Inverter Generator, Gas Powered, Parallel Capable, Long Run Time #ad
★★★★ 4.2 · 3K+ · $325
Pulsar 5,250W Dual Fuel Portable Generator with Switch and Go Technology, PG5250B #ad
★★★★☆ 4.6 · 276+ · $580
Westinghouse 5000 Peak Watt Super Quiet Portable Inverter Generator, Remote Electric Start with Auto Choke, Wheel & Handle Kit, RV Ready, Gas Powered, Parallel Capable #ad
★★★★☆ 4.7 · 5K+ ·
Honda Power Equipment EU3000IS 3000W 120V Portable Home Gas Power Generator #ad
★★★★☆ 4.6 · 109+ · $2399
Westinghouse 4650 Peak Watt Dual Fuel Portable Generator, Remote Electric Start with Auto Choke, RV Ready 30A Outlet, Gas & Propane Powered #ad
★★★★☆ 4.7 · 740+ · $440
Honda EU2200i 2200 Watt Inverter Generator, Super Quiet 120V Gas Powered Portable Generator for Camping or Home Backup Power Supply, Up to 8.1 Hour Run Time (EU2200ITAN) #ad
★★★★ 4.2 · 3K+ · $1199
DuroMax XP13000EH 13,000-Watt Dual Fuel Portable Generator - Gas & Propane, Electric Start, Whole Home Backup Power, Transfer Switch Ready, RV & Emergency Ready #ad
★★★★ 4.2 · 3K+ · $939
Pulsar 2,200W Portable Dual Fuel Quiet Inverter Generator with USB Outlet & Parallel Capability, CARB Compliant, PG2200BiS #ad
★★★★ 4.2 · 431+ · $325
YAMAHA EF2200iS Inverter Generator, 2200 Watts, Blue #ad
★★★★☆ 4.6 · 180+ · $1050
WEN Super Quiet 3800-Watt RV-Ready Portable Inverter Generator with Fuel Shut-Off and Electric Start (56380i) #ad
★★★★ 4.2 · 2K+ · $594
Westinghouse 12500 Watt Dual Fuel Home Backup Portable Generator, Remote Electric Start, Transfer Switch Ready, Gas and Propane Powered #ad
★★★★☆ 4.6 · 10K+ · $949
EGO POWER+ Portable Power Station, 3000W, Battery Powered, Inverter Generator for Home and Outdoor, Battery and Charger Not Included - PST3040 #ad
★★★★☆ 4.7 · 516+ · $499
WEN Super Quiet 2350-Watt Portable Inverter Generator with Fuel Shut Off, Gasoline Power, Ultra Lightweight (56235i), Black #ad
★★★★☆ 4.6 · 2K+ · $301
DuroMax XP13000HX 13,000-Watt Dual Fuel Portable Generator - Gas & Propane, Electric Start, Whole Home Power Backup, Transfer Switch Ready, RV & Emergency Ready #ad
★★★★☆ 4.6 · 1K+ · $1199
Champion Power Equipment 2500-Watt Ultralight Portable Dual Fuel Inverter Generator #ad
★★★★ 4.2 · 2K+ · $874
Briggs and Stratton 30747 3500 Watt Portable Generator 208cc OHV w/twistlock #ad
★★★★☆ 4.6 · 3 · $499
Honda EU3000iS 3000 Watt Inverter Generator, Super Quiet 120V Gas Powered Portable Generator for Camping, RV or Home Backup Power Supply, Up to 19.6 Hour Run Time (EU3000IS1AN) #ad
★★★★☆ 4.6 · 112+ · $2399
Honda EB5000 5000 Watt Generator, Quiet 120/240V Gas Powered OSHA-Compliant Portable Generator for Construction Site or Backup Power Supply, Up to 10.5 Hour Run Time (EB5000XK3AN) #ad
★★★★☆ 4.6 · 19 · $2799
Honda EU2200i 2200 Watt Inverter Generator, Super Quiet 120V Gas Powered Portable Generator for Camping or Home Backup Power Supply, Up to 8.1 Hour Run Time (EU2200ITAN) #ad
★★★★ 4.2 · 3K+ · $1199
DuroMax XP2300iH 2,300-Watt Dual Fuel Portable Digital Inverter Generator - Gas & Propane, RV & Emergency Ready #ad
★★★★ 4.2 · 100+ · $649
DuroMax XP13000HXT 13,000-Watt 500cc Tri Fuel Gas Propane Natural Gas Portable Generator with CO Alert, Black/Blue #ad
★★★★ 4.2 · 428+ · $1121
Westinghouse 2800 Peak Watt Super Quiet & Lightweight Portable Inverter Generator, Gas Powered, CO Sensor, Parallel Capable, Long Run Time #ad
★★★★ 4.3 · 440+ ·
Westinghouse Outdoor Power Equipment 14500 Peak Watt Dual Fuel Home Backup Portable Generator, Remote Electric Start, Transfer Switch Ready, Gas and Propane Powered #ad
★★★★ 4.2 · 2K+ · $1349
Westinghouse 5000 Peak Watt Super Quiet Dual Fuel Portable Inverter Generator, Remote Electric Start, Gas & Propane Powered, RV Ready, CO Sensor, Parallel Capable #ad
★★★★☆ 4.7 · 2K+ · $1069
Westinghouse 9500 Peak Watt Home Backup Portable Generator, Remote Electric Start with Auto Choke, Transfer Switch Ready, Gas Powered, CO Sensor #ad
★★★★ 4.2 · 6K+ ·
Westinghouse Outdoor Power Equipment 14500 Peak Watt Dual Fuel Home Backup Portable Generator, Remote Electric Start, Transfer Switch Ready, Gas and Propane Powered #ad
★★★★ 4.2 · 2K+ · $1349
Generac 7690 GP6500 6,500-Watt Gas-Powered Portable Generator - Powerrush Advanced Technology - Reliable Power for Emergencies and Recreation - 49-State Compliant #ad
★★★★☆ 4.6 · 3 · $703
Westinghouse 5000 Peak Watt Super Quiet Dual Fuel Portable Inverter Generator, Remote Electric Start, Gas & Propane Powered, RV Ready 30A Outlet, Parallel Capable, Blue/Black #ad
★★★★☆ 4.6 · 1K+ ·
Westinghouse 2800 Peak Watt Super Quiet & Lightweight Portable Inverter Generator, Gas Powered, Parallel Capable, Long Run Time #ad
★★★★ 4.2 · 3K+ · $549
Champion Power Equipment 3500-Watt Portable Inverter Generator with Quiet Technology and CO Shield #ad
★★★★☆ 4.6 · 205+ · $600
EF ECOFLOW Portable Power Station DELTA 2, 1024Wh LiFePO4 (LFP) Battery, 1800W AC/100W USB-C Output, Solar Generator(Solar Panel Optional) for Home Backup Power, Camping & RVs #ad
★★★★☆ 4.7 · 5K+ · $399
DuroMax XP15000HX 15,000-Watt Dual Fuel Portable Generator - Gas & Propane, Remote Electric Start, Whole Home Power Backup, Transfer Switch Ready, RV & Emergency Ready #ad
★★★★☆ 4.6 · 60 · $2499
Generac 3,300-Watt Gas Powered Portable Inverter Generator - Lightweight and Compact - USB Ports for Device Charging - Produces Clean, Stable Power - Great for Home Backup, Camping, and RV Use #ad
★★★★ 4 · 154+ ·
Champion Power Equipment 8125-Watt Electric Start Tri-Fuel Portable Generator with Free 3-Year Warranty #ad
★★★★ 4.2 · 28 · $999
Pulsar PGD40ISCO Ultra Light Quiet 4000W Portable Gas Inverter Generator, white #ad
★★★★ 4.2 · 467+ · $423
WEN 3600-Watt Portable Inverter Generator, RV-Ready, Quiet and Lightweight with Fuel Shut Off (56360i) #ad
★★★★ 4.2 · 567+ · $396
WEN 4800-Watt Portable Inverter Generator, Electric Start, RV-Ready, Quiet and Lightweight with Fuel Shut Off and CO Watchdog (56480iX) #ad
★★★★ 4.2 · 171+ · $679
WEN Quiet and Lightweight 4800-Watt RV-Ready Portable Inverter Generator with Fuel Shut Off (56477i) #ad
★★★★☆ 4.7 · 444+ · $555
Westinghouse 13500 Peak Watt Tri-Fuel Home Backup Portable Generator, Remote Electric Start, Transfer Switch Ready, Gas, Propane, and Natural Gas Powered #ad
★★★★☆ 4.6 · 2K+ ·
Pulsar 7,250-Watt Super Quiet Dual Fuel Inverter Generator with Remote Start #ad
★★★★ 4.2 · 113+ · $998
Champion Power Equipment 5000-Watt Electric Start Tri Fuel RV Ready Portable Generator with Free 3-Year Warranty #ad
★★★★☆ 4.8 · 98 · $688
Westinghouse 14500 Peak Watt Tri-Fuel Home Backup Portable Generator, Remote Electric Start, Transfer Switch Ready, Gas, Propane, and Natural Gas Powered #ad
★★★★ 4.2 · 2K+ ·
Champion Power Equipment 11,000-Watt Wireless Remote Start Home Backup Portable Inverter Generator with Quiet Technology and Free 3-Year Warranty #ad
★★★★☆ 4.6 · 106+ · $1789
Champion Power Equipment 2500-Watt Ultralight Portable Inverter Generator with Quiet Technology and Free 3-Year Warranty #ad
★★★★ 4.2 · 256+ · $549
Champion Power Equipment 9375-Watt Dual Fuel Portable Generator with Electric Start and Free 3-Year Warranty #ad
★★★★☆ 4.6 · 9 · $989
Champion Power Equipment 4500-Watt RV Ready Portable Inverter Generator with Quiet Technology and Free 3-Year Warranty #ad
★★★★★ 5 · 168+ · $679
Champion Power Equipment 4500-Watt Wireless Remote Start Inverter Generator with Quiet Technology and Free 3-Year Warranty #ad
★★★★☆ 4.6 · 59 · $946
Westinghouse 4000 Peak Watt Super Quiet Dual Fuel Portable Inverter Generator, Remote Electric Start, Gas & Propane Powered, RV Ready, CO Sensor, Parallel Capable #ad
★★★★☆ 4.6 · 2K+ · $549
Champion Power Equipment 2500-Watt Dual Fuel Portable Inverter Generator with Quiet Technology and CO Shield #ad
★★★★☆ 4.6 · 136+ · $584
DuroMax XP11000iH 11,000-Watt Dual Fuel Portable Digital Inverter Generator - Gas & Propane, Remote Electric Start, Transfer Switch Ready, RV & Emergency Ready #ad
★★★★ 4.2 · 34 · $1799
DuroStar DS13000MX 13,000-Watt 500cc Dual Fuel Portable Generator - Gas and Propane, Remote Electric Start, Whole Home Power Backup, Transfer Switch Ready, RV & Emergency Ready #ad
★★★★ 4.2 · 186+ · $899
Champion Power Equipment 11,000-Watt Wireless Remote Start Home Backup Portable Inverter Generator with Quiet Technology and Free 3-Year Warranty #ad
★★★★☆ 4.6 · 106+ · $1789
WEN 5,600-Watt Dual Fuel Portable Generator with Wheel Kit, Electric Start, and CO Watchdog (DF5600X) #ad
★★★★☆ 4.7 · 3K+ ·
AIVOLT 8000W Dual Fuel Inverter Generator, Super Quiet Electric Start Portable Generator Gas Propane Powered for Home Backup, RV, Camping & Travel - CARB Compliant #ad
★★★★☆ 4.7 · 379+ · $1100
Champion Power Equipment 4000-Watt RV Ready Portable Inverter Generator with Quiet Technology and Free 3-Year Warranty #ad
★★★★ 4.2 · 353+ · $585
Champion Power Equipment 4000-Watt Dual Fuel RV Ready Portable Inverter Generator with Quiet Technology and Free 3-Year Warranty #ad
★★★★ 4.2 · 248+ · $719
Champion Power Equipment 9375-Watt Electric Start Dual Fuel Home Backup Portable Generator with and CO Shield #ad
★★★★★ 5 · · $1000
Generac 3,300-Watt Gas Powered Portable Inverter Generator - Lightweight and Compact - USB Ports for Device Charging - Produces Clean, Stable Power - Great for Home Backup, Camping, and RV Use #ad
★★★★☆ 4.6 · 154+ ·
Generac 2,500-Watt Gas Powered Portable Inverter Generator - Lightweight and Compact Design - Produces Clean, Stable Power - Quiet Operation - Great for Home Backup, Camping, and RV Use #ad
★★★★ 4.2 · 73 ·
AMERISUN 4500W Open Frame Inverter Generator, 3800 Running Watts Portable Gas Powered Generator with CO Alert, RV Ready, Parallel Ready, Eco Mode, 223cc Engine for Home Backup, Camping & Emergency Use #ad
★★★★ 4.2 · 435+ · $210
Jackery Explorer 2000 v2 Portable Power Station, 2042Wh LiFePO4 Home Backup Battery, 2200W Solar Generator, USB-C PD 100W Fast Charging for Emergencies, Power Outages, Camping(Solar Panel Optional) #ad
★★★★☆ 4.7 · 763+ · $749
Champion Power Equipment 12,500-Watt Electric Start Tri Fuel Home Backup Portable Generator with Free 3-Year Warranty #ad
★★★★ 4.2 · 33 · $1260
Genkins 8000W Inverter Generator Outdoor Portable Generators Gas Powered Super Quiet with Electric Start Ideal for Home Backup, RV, Camping, Travel #ad
★★★★☆ 4.7 · 17 · $839
AFERIY 2048Wh Portable Power Station 2400W (Peak 4800W),P210 LiFePO4 Battery Generator,AC Fast Charging, 12V/25A XT60 DC output port,UPS Power Outages,Home Backup,Camping(Solar Panel Optional) #ad
★★★★☆ 4.7 · 335+ · $484
Generac 3,800-Watt Dual-Fuel Portable Inverter Generator - Gas and Propane Compatible - Quiet Operation - Clean, Stable Power - Great for Home Backup, Camping, and RV Use #ad
★★★★☆ 4.6 · 7 · $1049
Generac 8,000-Watt Gas-Powered Portable Generator - COsense Technology - Powerrush Advanced Technology - Power for Emergencies and Recreation - Electric Start - Orange/Black - 50 State Compliant #ad
★★★★☆ 4.6 · 2 · $1283
Generac 12,500 Starting Watt Tri-Fuel Portable Generator - Electric Start - Gas, Propane or Natural Gas - Home Backup, Jobsite, or RV - Quiet Operation - Long Runtime - 50-State Compliant #ad
★★★★☆ 4.6 · 26 · $1399
WEN 6800-Watt Dual Fuel RV-Ready Electric Start Portable Inverter Generator with Fuel Shut Off and CO Watchdog for Electric Vehicle Backup (DF680iX) #ad
★★★★☆ 4.7 · 309+ ·
Westinghouse 5000 Peak Watt Super Quiet Dual Fuel Portable Inverter EFI Generator, Remote Electric Start, Gas & Propane Powered, RV Ready, CO Sensor, Parallel Capable, CARB Compliant #ad
★★★★☆ 4.7 · 80 · $1249
Westinghouse Outdoor Power Equipment 14500 Peak Watt Dual Fuel Home Backup Portable Generator, Remote Electric Start, Transfer Switch Ready, Gas and Propane Powered #ad
★★★★ 4.2 · 2K+ · $1349
Pulsar 13,000-Watt Tri Fuel Gasoline, Propane, Natural Gas, Portable Generator with Remote Start #ad
★★★★☆ 4.6 · · $1199
Champion 3650-Watt RV-Ready Portable Generator with CO Shield #ad
★★★★☆ 4.6 · · $420
Westinghouse 7500 Peak Watt EFI Dual Fuel Home Backup Portable Generator, Remote Electric Start, Transfer Switch Ready, Gas and Propane Powered, CO Sensor, CARB Compliant #ad
★★★★ 4.2 · 6K+ · $1049
DuroMax XP11000iHT 11,000-Watt Tri Fuel Portable Digital Inverter Generator - Gas, Propane & Natural Gas, Remote Electric Start, Whole Home Power Backup, Transfer Switch Ready, RV & Emergency Ready #ad
★★★★☆ 4.7 · 1 · $2641
Westinghouse 8200 Peak Watt Tri-Fuel Portable Inverter Generator, Remote Electric Start, Transfer Switch Ready, Gas, Propane, Natural Gas, Low THD, Safe for Electronics, Parallel Capable, CO Sensor #ad
★★★★☆ 4.6 · 196+ · $1399
Anker SOLIX C1000 Gen 2 Portable Power Station, 2,000W (Peak 3,000W) Solar Generator, Full Charge in 49 Min, 1,024Wh LiFePO4 Battery for Home Backup, Power Outages, and Camping (Optional Solar Panel) #ad
★★★★★ 5 · 1K+ · $400
Oxseryn 5000W Inverter Generator Gas Powered, Open Frame Generator, Portable Outdoor Power Equipment, Emergency Home Backup, RV Ready 30A Outlet, ECO Mode, EPA Compliant #ad
★★★★★ 5 · 304+ · $323
Champion Power Equipment 5500-Watt RV Ready Portable Generator | Open Frame Inverter, Quiet Technology, 3-Year Warranty, CARB Compliant #ad
★★★★☆ 4.5 · · $679
PowerSmart 3800 Watt Dual Fuel Inverter Generator, Quiet Portable Gas Propane Powered with CO Sensor and RV, 149cc 4-Stroke OHV Engine for Home Backup, Camping and Tailgating #ad
★★★★★ 5 · 1K+ · $427
Anker SOLIX C2000 Gen 2 Portable Power Station, 2,400W (Peak 4,000W) Solar Generator, Full Charge in 58 Min, 2048wh LiFePO4 Battery for Home Backup, Power Outages, and Camping (Optional Solar Panel) #ad
★★★★★ 5 · 365+ · $800
Oxseryn 5000-Watts Portable Inverter Generator, Gas Generator for Home Backup, 30A Outlet, RV Ready, ECO Mode, 60Lbs, EPA Compliment #ad
★★★★★ 5 · 14 · $304
Generac 12,500 Starting Watt Tri-Fuel Portable Generator, Electric Start, Gas Propane Natural Gas, COsense Carbon Monoxide Detection, 9.5 Hour Runtime, Home Backup Emergency, 49-State Compliant #ad
★★★★☆ 4.6 · 32 ·
Champion Power Equipment 8500-Watt Wireless Remote Start Ultra Quiet Tri Fuel RV Ready Portable Inverter Generator with StartLINK, Free 3-Year Warranty #ad
★★★★ 4 · 3 · $1389
Oxseryn 2800-Watts Portable Inverter Generator, Gas Generators for Home Use, Camping, Super Quiet Emergency Home Backup, with Fuel Shut Off, 1.1Gal Fuel Tank, 39Lbs, EPA Compliant #ad
★★★★★ 5 · 376+ · $285
Best Standby Generators
Champion Power Equipment 100177 8.5-kW Home Standby Generator with 50-Amp Outdoor-Rated Automatic Transfer Switch #ad
★★★★☆ 4.6 · 57 · $3649
Generac Guardian 10kW Home Standby Generator with 100 Amp Transfer Switch - Automatic Whole House Backup Power for Storms, Emergencies, and Outages, WiFi Enabled, Runs on Natural Gas or Liquid Propane #ad
★★★★ 4.2 · 38 · $4119
14kW Standby Generator with 200amp TS #ad
★★★★☆ 4.6 · · $5839
Generac Guardian 26kW Home Standby Generator with 200 Amp Transfer Switch - Automatic Whole House Backup Power for Storms, Emergencies, and Outages, WiFi Enabled, Runs on Natural Gas or Liquid Propane #ad
★★★★ 4.2 · 56 · $7749
Honeywell 14kW Home Standby Generator #ad
★★★★★ 5 · · $4859
Honeywell 18kW Home Standby Generator #ad
★★★★☆ 4.6 · 1 · $5819
Generac 18kW Home Standby Generator for home use, built-in cellular connectivity, whole house generator for power backup #ad
★★★★☆ 4.6 · 2 · $5039
Generac 22kW Home Standby Generator for home use, built-in cellular connectivity, whole house generator for power backup #ad
★★★★★ 5 · · $5570
Generac 22kW Home Standby Generator for home use with 200 amp transfer switch, built-in cellular connectivity, whole house generator for power backup #ad
★★★★★ 5 · · $6506
Generac 26kW Home Standby Generator for home use, built-in cellular connectivity, whole house generator for power backup #ad
★★★★★ 5 · · $6317
Generac 24kW Home Standby Generator for home use, built-in cellular connectivity, whole house generator for power backup #ad
★★★★★ 5 · · $5039
Generac 24kW Home Standby Generator for home use with 200 amp transfer switch, built-in cellular connectivity, whole house generator for power backup #ad
★★★★☆ 4.5 · 1 · $6875
Generac 10kW Home Standby Generator with 16 circuit transfer switch, cellular connectivity, easy to use, whole house power backup, smart outage solution #ad
★★★★☆ 4.6 · · $3896
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Generator Wattage FAQ
What’s the difference between running watts and starting watts?
Running watts (rated watts) is the continuous power a device draws while operating. Starting watts (surge watts) is the short burst needed to start motors — typically 2–7× running watts, lasting 2–3 seconds. Always size your generator for the running total plus the largest single starting surge.
What size generator do I need for my house?
For essential circuits (fridge, sump pump, furnace, lights): 5,000–7,500 watts. For most of a 2,000 sq ft home including window AC: 7,500–10,000 watts. Whole-home including central AC: 20,000–26,000 watts (standby). Use our free calculator for your exact number.
Do I add ALL starting surges together?
No. NEC 702 practice is to add only the largest single starting surge to the total running watts. Multiple motors don’t start simultaneously in normal operation. Adding all surges together would unnecessarily oversize your generator.
Portable vs standby generator — which should I choose?
Portable ($400–$3,000): manual setup, runs on gas/propane, powers select circuits via extension cords or transfer switch. Standby ($5,000–$12,000 installed): auto-start within seconds, runs on natural gas/propane, powers entire home. See our full portable vs standby comparison.
Get Your Exact Generator Size in 60 Seconds
Check off what you need to power and our NEC 702-based calculator gives you the exact wattage — plus the best generator to buy.
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