How to read this chart

Six columns, six different questions.

Running is what an appliance pulls while it is working. It is the nameplate figure, and what a generator has to hold steady for hours.

Starting is the split second when a motor or compressor spins up, at two to five times running watts. Resistive items, meaning anything that is really just a heating element, have no inrush: their starting figure equals their running figure, and that is not a mistake in the table. Starting watts versus running watts has the full story.

Average is the draw once cycling is counted. A refrigerator compressor runs about a third of an hour; a kettle is on for three minutes. This column weights running watts by that duty fraction and adds back idle draw for anything holding a boiler hot.

Per hour is the same measurement read as energy: average watts sustained for an hour equals that many watt-hours. They track each other, but energy is what empties a battery, so it gets its own column.

Amps is running watts divided by 120 volts. A 15 amp circuit is designed to carry about 12 amps continuously, a 20 amp circuit about 16. That 80 percent figure is the rule of thumb electricians work to, and it is why a heater and a coffee maker on one kitchen circuit trip the breaker.

The amps column is calculated at each item's own supply voltage, so the 240 volt equipment here, including electric ranges, water heaters, dryers, well pumps and commercial fryers, shows the amps it actually pulls on its two-pole circuit rather than an inflated 120 volt figure. Compare those amps against the breaker feeding the circuit, not against the generator.

A nameplate is a ceiling, not an average

The number printed on an appliance is the most it will ever draw, at its hardest working moment. Almost nothing lives there. That gap is why people buy a 5,000 watt generator for a 2,000 watt problem. The running column tells you how big the source must be; the per hour column tells you how long it lasts. The watts calculator does both at once, including the surge maths.

Everything below is a typical figure for a typical unit. If the appliance you own has a label, use the label. This chart exists for when it does not.

Cooling & refrigeration

Everything here has a compressor or a motor, so the starting column is always the higher one. A refrigerator rated at 150 watts asks for 750 for an instant, which is why a small inverter that carries a fridge all day can still refuse to start it. Notice how far the average column sits below running for the fridges and freezers, and how close it sits for the air conditioners, which barely rest on a hot day. There is a full breakdown in how many watts a refrigerator uses.

ApplianceRunningStartingAveragePer hourAmps
Refrigerator (18–22 cu ft)150 W750 W55 W50 Wh1.3 A
Mini fridge (3–5 cu ft)80 W320 W30 W30 Wh0.7 A
Chest freezer (7–15 cu ft)120 W600 W40 W40 Wh1.0 A
Upright freezer160 W800 W60 W60 Wh1.3 A
Window air conditioner (5,000 BTU)500 W1,500 W350 W350 Wh4.2 A
Window air conditioner (8,000 BTU)720 W2,150 W500 W500 Wh6.0 A
Window air conditioner (12,000 BTU)1,100 W3,300 W770 W770 Wh9.2 A
Portable air conditioner (10,000 BTU)1,000 W2,800 W750 W750 Wh8.3 A
Central A/C (2 ton)2,500 W7,500 W1,500 W1.50 kWh10 A
Central A/C (3 ton)3,500 W10,500 W2,100 W2.10 kWh15 A
Box or pedestal fan75 W150 W75 W80 Wh0.6 A
Ceiling fan60 W120 W60 W60 Wh0.5 A

Heating & climate

The mirror image. An electric space heater draws 1,500 watts with no surge at all and is still the fastest way to flatten a battery on this page. The row people miss is the gas furnace blower: the furnace burns gas, but the blower is an electric motor, and in an outage that motor is what you are actually powering. It surges to nearly 2,350 watts, often the largest single spike on a home backup list.

ApplianceRunningStartingAveragePer hourAmps
Gas furnace blower (1/2 hp)800 W2,350 W290 W290 Wh6.7 A
Electric space heater1,500 W1,500 W900 W900 Wh13 A
Pellet stove300 W800 W200 W200 Wh2.5 A
Electric blanket180 W180 W70 W70 Wh1.5 A
Boiler circulation pump120 W360 W70 W70 Wh1.0 A
Dehumidifier480 W1,450 W290 W290 Wh4.0 A

Home kitchen

Kitchen appliances have the highest running watts in a house and some of the lowest energy use, because they run for minutes at a time. An electric kettle is 1,500 watts running and about 60 watts averaged across an hour. Two traps: the wattage on a microwave door is cooking power, not draw, so a 1,000 watt microwave pulls roughly 1,500 watts from the outlet; and a portable induction burner at 1,800 watts lands at exactly 15 amps, so it needs a 20 amp outlet to itself.

ApplianceRunningStartingAveragePer hourAmps
Microwave (1,000 W cooking)1,500 W1,500 W120 W120 Wh13 A
Drip coffee maker900 W900 W270 W270 Wh7.5 A
Electric kettle1,500 W1,500 W60 W60 Wh13 A
Toaster1,100 W1,100 W45 W40 Wh9.2 A
Air fryer1,500 W1,500 W750 W750 Wh13 A
Portable induction burner1,800 W1,800 W900 W900 Wh15 A
Dishwasher1,200 W1,800 W540 W540 Wh10 A
Electric range element2,400 W2,400 W1,200 W1.20 kWh10 A
Slow cooker250 W250 W150 W150 Wh2.1 A
Rice cooker (commercial 20 cup)1,550 W1,550 W580 W580 Wh13 A

Water & sanitation

Pumps are why home generators get sized up. A 1/3 horsepower sump pump runs at 800 watts and starts at 2,400, yet uses almost no energy over a day because it works in short bursts. Size for the surge, then budget energy on how often it kicks in. The dryer, the tank water heater and both well pumps run on 240 volts, and their amps below are shown at 240, which is why the figures look modest next to their wattage.

ApplianceRunningStartingAveragePer hourAmps
Sump pump (1/3 hp)800 W2,400 W65 W60 Wh6.7 A
Sump pump (1/2 hp)1,050 W3,150 W85 W80 Wh8.8 A
Well pump (1/2 hp)1,000 W3,000 W40 W40 Wh4.2 A
Well pump (1 hp)2,000 W6,000 W80 W80 Wh8.3 A
Electric water heater (tank)4,500 W4,500 W900 W900 Wh19 A
Clothes washer500 W1,400 W200 W200 Wh4.2 A
Clothes dryer (electric)5,000 W6,750 W4,000 W4.00 kWh21 A
Hand-wash station water heater1,400 W1,400 W140 W140 Wh12 A

Lights & electronics

Put every light, screen and charger in a house together and the total is still smaller than one air fryer. It is the category worth keeping on a battery. The outlier is the garage door opener, at 550 watts running and 1,650 starting but about 10 watts averaged over an hour, because it works for seconds a day. If you run a CPAP on battery, switch the heated humidifier off.

ApplianceRunningStartingAveragePer hourAmps
LED lighting (10 bulbs)90 W90 W90 W90 Wh0.8 A
TV (55" LED)100 W100 W100 W100 Wh0.8 A
Laptop65 W65 W55 W50 Wh0.5 A
Phone charging (per phone)20 W20 W10 W10 Wh0.2 A
Wi-Fi router and modem15 W15 W15 W20 Wh0.1 A
Starlink dish60 W120 W55 W60 Wh0.5 A
CPAP machine (no humidifier)40 W40 W40 W40 Wh0.3 A
CPAP with heated humidifier90 W90 W65 W60 Wh0.8 A
Garage door opener550 W1,650 W10 W10 Wh4.6 A
Security system / cameras30 W30 W30 W30 Wh0.3 A

Food truck & coffee cart

The biggest list here, and the one most charts get wrong. Commercial espresso machines are quoted at their element rating, but the boiler idles near 180 watts holding temperature and only pulls the full load while recovering after a shot. The commercial blender has the worst surge-to-energy ratio on the site: 4,500 watts to start, about 75 watts averaged over an hour. Fryers and griddles are the reverse, resistive so nothing surges, but they hold a high average all service. Do not forget the hood fan, which runs flat out from open to close.

ApplianceRunningStartingAveragePer hourAmps
Espresso machine (1 group, commercial)1,800 W1,800 W500 W500 Wh15 A
Espresso machine (2 group, commercial)2,800 W2,800 W930 W930 Wh12 A
Espresso machine (prosumer, single boiler)1,350 W1,350 W280 W280 Wh11 A
Commercial batch brewer1,600 W1,600 W560 W560 Wh13 A
Espresso grinder (on demand)400 W1,200 W20 W20 Wh3.3 A
Commercial blender1,500 W4,500 W75 W80 Wh13 A
Electric fryer (single basket)3,500 W3,500 W1,400 W1.40 kWh15 A
Electric fryer (double basket)5,000 W5,000 W2,250 W2.25 kWh21 A
Electric griddle (24")3,000 W3,000 W1,350 W1.35 kWh13 A
Electric griddle (36")4,500 W4,500 W2,050 W2.02 kWh19 A
Panini press / sandwich grill1,800 W1,800 W730 W730 Wh15 A
Steam table (3 well)1,500 W1,500 W790 W790 Wh13 A
Countertop food warmer800 W800 W380 W380 Wh6.7 A
Refrigerated prep table400 W1,600 W160 W160 Wh3.3 A
Undercounter commercial fridge350 W1,400 W140 W140 Wh2.9 A
Undercounter ice machine600 W1,800 W320 W320 Wh5.0 A
Soft-serve machine (countertop)1,800 W5,400 W1,050 W1.02 kWh15 A
Slushie / granita machine (2 bowl)1,100 W3,300 W740 W740 Wh9.2 A
Exhaust hood fan500 W1,500 W500 W500 Wh4.2 A
POS terminal and card reader60 W60 W60 W60 Wh0.5 A
Hot dog roller1,100 W1,100 W620 W620 Wh9.2 A
Popcorn machine (8 oz)1,400 W1,400 W680 W680 Wh12 A
Cotton candy machine1,050 W2,100 W530 W530 Wh8.8 A
Commercial waffle iron1,400 W1,400 W680 W680 Wh12 A
Countertop electric pizza oven3,200 W3,200 W1,800 W1.80 kWh13 A
Heated holding cabinet1,600 W1,600 W660 W660 Wh13 A

Events & market stalls

Amplifier ratings are the thing to watch. The wattage printed on a PA system is peak music power, and average draw across a set is far lower. The bounce house blower is the opposite surprise: it runs flat out the entire time the inflatable is up, with no duty cycle to save you, and surges to 2,700 watts. An electric patio heater quietly out-consumes everything else on a stall.

ApplianceRunningStartingAveragePer hourAmps
PA system (small, 2 speakers)200 W400 W150 W150 Wh1.7 A
PA system (band / DJ rig)900 W1,800 W650 W650 Wh7.5 A
LED stage / market lighting300 W450 W300 W300 Wh2.5 A
String lights (100 ft LED)50 W50 W50 W50 Wh0.4 A
Projector300 W400 W300 W300 Wh2.5 A
Electric patio heater1,500 W1,500 W1,200 W1.20 kWh13 A
Misting fan200 W500 W200 W200 Wh1.7 A
Bounce house blower900 W2,700 W900 W900 Wh7.5 A
Photo booth (printer + screen)350 W700 W250 W250 Wh2.9 A

RV & camping

Compare the three air conditioner rows and you have the whole soft start argument in one place. A 13,500 BTU roof unit runs at 1,400 watts either way, but the surge falls from 3,500 to 1,800 with a soft start kit, the difference between needing a 3,500 watt generator and getting by with a 2,200. The fridge rows matter too: an absorption fridge on electric draws several times what a 12 volt compressor fridge does.

ApplianceRunningStartingAveragePer hourAmps
RV air conditioner (13,500 BTU)1,400 W3,500 W980 W980 Wh12 A
RV air conditioner (15,000 BTU)1,700 W4,000 W1,200 W1.19 kWh14 A
RV air conditioner with soft start (13,500 BTU)1,400 W1,800 W980 W980 Wh12 A
RV converter / battery charger450 W450 W280 W280 Wh3.8 A
RV water pump60 W180 W6 W10 Wh0.5 A
RV fridge (absorption, on electric)330 W330 W200 W200 Wh2.7 A
RV fridge (12 V compressor)60 W240 W25 W30 Wh0.5 A
RV water heater (electric element)1,400 W1,400 W280 W280 Wh12 A
RV microwave1,000 W1,000 W85 W80 Wh8.3 A
RV TV and satellite receiver90 W90 W90 W90 Wh0.8 A
12 V electric cooler45 W180 W20 W20 Wh0.4 A

Tools & jobsite

Power tools use very little energy and demand enormous peaks. A miter saw spends a few seconds per cut actually cutting, so its hourly figure is tiny, but it wants 3,600 watts the moment you pull the trigger. The air compressor is worse because it starts against tank pressure: a 1,500 watt motor asks for 4,500. On a jobsite the real risk is two trades pulling triggers at once, the one case where the single-surge rule can let you down.

ApplianceRunningStartingAveragePer hourAmps
Circular saw (7-1/4")1,400 W2,500 W170 W170 Wh12 A
Miter saw (10–12 in)1,800 W3,600 W140 W140 Wh15 A
Table saw (contractor)1,800 W4,500 W270 W270 Wh15 A
Air compressor (2 hp)1,500 W4,500 W450 W450 Wh13 A
Electric pressure washer1,400 W3,500 W840 W840 Wh12 A
Wet tile saw1,200 W2,400 W360 W360 Wh10 A
LED work lights (pair)100 W100 W100 W100 Wh0.8 A
Cordless tool battery charger100 W100 W70 W70 Wh0.8 A
MIG welder (140 A, 120 V)3,000 W3,000 W640 W640 Wh25 A

Turning the chart into an answer

Reading watts off a table is the easy half. The work is adding them up correctly: total the running watts of everything that can be on at once, add one surge rather than all of them, then use the per hour column to work out how long a tank or a battery lasts. Three sums, three different rules, and it is exactly what the sizing calculator does when you tick the same items off this list.