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How many watts does a microwave use?

A typical microwave uses 1,050–1,700 watts when running and draws 8.8–14.2 amps at 120 volts.

Microwave watts, amps and circuit

Typical power use of a microwave
Running watts1,050–1,700 W
Voltage120 V
Running amps8.8–14.2 A
Circuit20 A breaker, dedicated circuit
Wire size (copper, NM-B cable)12 AWG

Also called: microwave oven, small microwave.

Microwave watts by size and type

Running and starting watts of microwave types
Size or typeRunning watts, WVolts, VAmps, AStarting watts, W
Microwave1,050–1,7001208.8–14.2—
700 W cooking power1,0501208.8—
900 W cooking power1,0501208.8—
1,000 W cooking power1,500–1,70012012.5–14.2—
1,100 to 1,150 W cooking power1,600–1,65012013.3–13.8—
1,200 W cooking power1,65012013.8—
01,0002,000Watts, WSize or typeMicrowaveMicrowave, Running watts: 1,050–1,7001,050–1,700700 W cooking power700 W cooking power, Running watts: 1,0501,050900 W cooking power900 W cooking power, Running watts: 1,0501,0501,000 W cookingpower1,000 W cooking power, Running watts: 1,500–1,7001,500–1,7001,100 to 1,150 Wcooking power1,100 to 1,150 W cooking power, Running watts: 1,600–1,6501,600–1,6501,200 W cookingpower1,200 W cooking power, Running watts: 1,6501,65005001,0001,5002,000Watts, WSize or typeMicrowaveMicrowave, Running watts: 1,050–1,7001,050–1,700700 W cooking power700 W cooking power, Running watts: 1,0501,050900 W cooking power900 W cooking power, Running watts: 1,0501,0501,000 W cooking power1,000 W cooking power, Running watts: 1,500–1,7001,500–1,7001,100 to 1,150 W cooking power1,100 to 1,150 W cooking power, Running watts: 1,600–1,6501,600–1,6501,200 W cooking power1,200 W cooking power, Running watts: 1,6501,650
Watts of microwave types. The lighter part of a bar is the upper end of the typical range.

What size generator runs a microwave?

A microwave needs a generator that supplies at least 1,700 running watts. A 2,000 W generator covers it with its running rating alone; add the watts of anything else you run at the same time.

How long a portable power station runs a microwave

Runtime of a microwave on a portable power station, at 85% inverter efficiency
Battery capacity, WhAt 1,700 W, hAt 1,050 W, h
5000.30.4
1,0000.50.8
2,00011.6
3,6001.82.9

A 500 Wh portable power station runs a microwave drawing 1,700 W for about 0.3 hours at 85% inverter efficiency. Runtime = capacity × 85% ÷ watts; the 85% efficiency is an assumption. The power station's AC output must be at least 1,700 W.

What it costs to run a microwave

Running a microwave at 1,375 W, the middle of its 1,050–1,700 W range, for one hour a day uses 501.9 kWh a year. That costs about $90 a year at $0.18 per kWh, the US average residential price for August 2026.

W
h
$/kWh

Your bill's total ÷ kWh used. 0.18 is the US residential average.

Result
$7.53 / month
Per day
$0.25
Per year
$90
Energy per day
1.38 kWh
Energy per month
41.8 kWh

How it is calculated

  1. kWh per day = 1,375 W × 1 h ÷ 1,000 = 1.375
  2. Per month = 1.375 kWh × 30.4 days × $0.18 = $7.53

What affects microwave power use

The wattage printed on the front of a microwave is cooking power. The oven draws roughly 1.2 to 1.7 times that from the wall, which is why a 1,100 W microwave can pull about 1,650 W. GE asks for an over-the-range model to be plugged into a separate 15 or 20 A branch circuit; a countertop model plugs into a kitchen countertop outlet.

How the amps are calculated

Amps = watts ÷ volts. For 1,700 W at 120 V that is 14.2 A. The 1,050–1,700 W range covers typical models; the nameplate on a microwave gives the exact figure.

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