How many watts does a microwave use?
A common microwave draws **1200 to 1500 watts** from the wall. That is not the number printed on the front of it. The front panel shows **cooking power** — usually 700 to 1000 watts. The draw is roughly half again as much, because turning electricity into microwaves is not free. Both numbers are real and they answer different questions.
Work it out with your own tariff
Minutes a day
Watts, from the label on yours
Your rate, cents per kWh
| Period | Cost | Time counted |
|---|---|---|
| One minute | $0.0024 | 1 minute |
| Your daily use | $0.0240 | 10 minutes a day |
| A month | $0.72 | × 30 days |
| A year | $8.76 | × 365 days |
1200 W × 10 min ÷ 60 ÷ 1000 = 0.2000 kWh × 12¢ = $0.0240 a day.
Minutes are counted per day in total, not per use. If you use it three times a day for two minutes, that is six. The distinction matters because multiplying one use by 365 assumes you use it once a day, and most pages that quote a yearly figure never say which they did. 1200-1500 W is what a common microwave draws from the wall, which is not the number printed on the front. The front panel shows cooking power — 700 to 1000 W on most models — and the draw is roughly half again as much. The figure you need is on the rating label, usually on the back or inside the door frame. Rate defaults to 18.44¢ (U.S. Energy Information Administration, 2026-05).
Which number is which
| Number | Where it is | What it means |
|---|---|---|
| Cooking power | Front panel, adverts, the box | How much energy reaches the food |
| Input power | Rating label, back or door frame | How much it draws from the socket |
For electricity costs and for anything about circuits, you need the second one. A microwave advertised as 1000 W typically draws around 1500 W.
This is why the amps question has a wrong answer everywhere
"How many amps does a 1000-watt microwave use" is a common question, and the common answer is arithmetic on the wrong number:
- Using the advertised 1000 W: 1000 ÷ 120 = 8.3 amps
- Using the actual draw of 1500 W: 1500 ÷ 120 = 12.5 amps
The gap is fifty per cent, and it is the difference between "this shares a circuit fine" and "this trips the breaker when the kettle is on". If you are sizing a circuit, a generator or an inverter, the 8.3 figure will let you down.
What it costs
At 1500 W a single minute costs about half a cent. Ten minutes a day — which is a lot of microwaving — comes to roughly $17 a year.
Set your own numbers below. Take the watts from the rating label rather than the front panel, and count minutes per day in total rather than per use: a microwave gets opened several times a day, and multiplying one use by 365 assumes it gets opened once.
Standby is not counted here and it is not nothing
A microwave with a clock draws a small amount continuously, and over a year the clock can rival the cooking. We do not publish a figure for it because no certification programme measures microwave standby and the range across models is wide — anywhere from under a watt to several. If yours has a bright display and lives on a kitchen counter, that draw is real and this page does not include it.
What this does not account for
The number on the front is not the draw. This is the single most common error on this topic, and it runs in the direction that understates: the advertised figure is always lower than the real one.
No source, and there cannot be one. Microwaves are not certified for energy use by any programme we could cite, so the figure is the rating label on your own appliance. Any page quoting a measured wattage for microwaves in general has not measured anything.
Standby is excluded. The clock and display draw continuously and are not in these figures. For a microwave used briefly but plugged in permanently, standby can be the larger half of the annual total.
Efficiency varies and we do not model it. The relationship between cooking power and draw is not a fixed ratio across models. Use the rating label rather than multiplying the front-panel number by a rule of thumb.
Worth reading next
Sources
- 01Electric Power Monthly, Table 5.3 — average price of electricity to ultimate customersU.S. Energy Information Administration ·
How these figures are produced: see our methodology.
Figures are calculated from published wattages and a published tariff, both dated above. They are good for comparing devices, not for predicting your bill: your rate, settings and usage all differ.