What noises does a microwave make?
A microwave makes four kinds of noise: its beeps, its door, the hum while it cooks and, on over-the-range models, the vent fan.
Beeps
Keypad tones, the end-of-cooking signal and, on some models, a reminder that repeats until you open the door. Whether you can switch these off varies by model, and it is rarely mentioned on the product page. It is in the owner's manual.
Microwave doors open with either a push button or a pull handle. Only Breville makes a specific claim about door noise, for its soft-close models. Drawer microwaves have no swinging door at all.
The cooking hum
Every microwave hums, and almost no manufacturer says how loudly. Breville publishes figures for one model, and LG's support site gives a general range.
The vent fan
Over-the-range microwaves double as a range hood, and their fans carry certified noise ratings in sones, just as range hoods do.
How do you turn off the beep on a microwave?
Turning off a microwave's beep depends on the model: Breville has a dedicated mute button, Toshiba and GE mute from the keypad or a settings menu, and some Panasonic and Whirlpool signals cannot be turned off at all.
This is the easiest fix and the one most worth checking before you buy. What the manuals say:
Breville has a dedicated mute button.
On the Compact Wave, the display shows OFF when tones are silenced.
Toshiba's ML-EM45PIT mutes with a three-second press of the 8 key, which turns off both keypad and end-of-cooking sounds.
Sharp's microwave drawer has a setting it calls Audible Signal Elimination.
GE models generally have a sound or beeper volume pad, a sound level in the settings menu, or a mute pad, depending on the model. The GE Profile PVM9179 offers mute, low, normal and loud.
Samsung generally puts sound on/off under its options menu, though the steps vary by model.
Panasonic's NN-SN686S can have its beep switched off only in the moments after it is plugged in, and Panasonic says the beep on its NN-CS597 cannot be turned off at all.
Whirlpool says most audible signals on its over-the-range microwaves cannot be turned off.
Galanz's retro model has no mute in its manual, and its end-of-cooking reminder repeats every two minutes. The manuals for the Commercial Chef CHM990B and Farberware FMO11AHTBKB have no mute procedure either.
If beeps are your main complaint, download the manual for the exact model before you buy, and search it for "mute," "sound" or "beep."
Which microwave has the quietest door?
Breville's soft-close door is the only microwave door with a published figure: Breville cites an independent lab test putting the Compact Wave's door at 81.5 dBA, against 99.6 dBA for its older BMO735.
Breville is the only manufacturer we found that treats door noise as something to engineer and measure. Both of our Breville picks share that door.
No other brand we checked makes a quiet-door claim, and we found no manufacturer comparing push-button and pull-handle latches for noise. If you cannot stretch to a Breville, the only answer is that you will have to try the door in a store.
Drawer microwaves sidestep the problem. Sharp's drawer opens at the press of a button and closes itself after a nudge. Sharp makes no noise claim for it, and it costs several times as much as a countertop model, so it makes sense mainly as part of a remodel.
How many decibels is a microwave while it cooks?
A microwave makes about 45 to 50 dB of vibration noise, according to LG's support site, which says this is normal.
The hum comes from the parts that do the work. According to GE, the magnetron cycles on and off at anything below full power, which you hear as thumping, clicking or humming, and a cooling fan runs during cooking and for a few seconds after.
Whirlpool attributes the hum to the cooling fan and the power supply switching the magnetron. Samsung adds that the noise may get slightly louder as the oven ages.
Breville is the only brand with a figure for a specific model: 56.4 dBA for the Combi Wave, against 59.7 dBA for its older microwave. Those numbers come from different sources with no shared method, so do not read them as the Breville being louder than an LG.
One idea we could find no support for: that inverter microwaves are quieter. Panasonic, LG and Breville all sell inverter models, and all describe the benefit as smoother, more even heating. None claims it is quieter.
With so few published figures, the best independent evidence is Consumer Reports, which tests noise as part of its microwave ratings. It rates the LG NeoChef MSER1590S excellent for noise while cooking.
How loud is an over-the-range microwave fan?
Most over-the-range microwave fans are certified at 6 to 8.5 sones at high speed, and the quietest high-speed ratings we found were about 4 to 5 sones.
An over-the-range microwave's vent fan is rated the same way a range hood is, in sones, a scale on which a 2 sone fan is heard as double a 1 sone fan. The ratings are in two public directories: the Home Ventilating Institute's, and the Association of Home Appliance Manufacturers', which covers Whirlpool, GE, LG, Samsung and their sister brands.
Two things stand out in those directories.
They are loud on high
Most over-the-range fans are certified at 6 to 8.5 sones at high speed, and 1 to 3 sones at their working speed of around 100 CFM. The quietest high-speed ratings we found were about 4 to 5 sones, on a handful of Frigidaire, Whirlpool and GE models that are either no longer made or whose availability we could not confirm.
The advertised airflow is not the certified airflow
Bosch markets the HMV8054U at 385 CFM; it is certified at 280. Samsung's ME19R7041FS is sold as 400 CFM and certified at 310. LG, Whirlpool and Frigidaire models sold as 400 CFM are certified between 250 and 310.
If your kitchen allows it, a separate range hood can be quieter and move more air: the quietest hood in our range hood guide moves 470 CFM with a 4 sone certification.
If it doesn't, compare the certified sones at the speed you will actually use, and remember that Consumer Reports scores cooking noise and venting noise separately for these models. Where the microwave hangs over a cooktop that the living room can hear, the range hood guide's open-plan method for finding the sone rating at your usual cooking step applies just as well.
Is it normal for a microwave to make noise?
Yes, most microwave sounds are harmless, from relay clicks at the start of cooking to turntable clicks and food popping, but a few are worth acting on.
GE lists relay clicks at the start of cooking, the hum of the clock transformer on standby, and on over-the-range models a vent damper click and a fan that switches itself on when the cooktop below gets hot. Samsung says turntable clicks and food popping are normal too.
These are the ones to act on:
Thumping or rumbling usually means the turntable or its roller support is dirty or out of place. Whirlpool's advice is to clean and reseat them. Panasonic's and Breville's manuals say the same about a dirty roller ring.
Rattling, according to LG, often comes from the installation, an uneven surface, or something stored on top of the microwave.
A hum that is noticeably louder than a month ago, rattling that continues after you reseat the filters, or popping that continues after cleaning all call for service, according to Samsung.
Samsung also warns never to run a microwave empty.
Which microwave mistakes leave you with a noisy kitchen?
Five microwave buying mistakes lead to a noisy kitchen: assuming every model can be muted, paying for an inverter to get quiet, trusting the CFM on the box, ignoring the door and treating a new noise as normal.
Assuming every microwave can be muted
Some can't, and the product page won't tell you. The manual will.
Paying for an inverter to get quiet
Inverters heat more evenly. No maker says they are quieter.
Trusting the CFM on the box
For over-the-range models, the certified airflow in our examples was 20% to 40% lower than the marketing figure.
Ignoring the door
You will close it thousands of times. If you can, try it in a store.
Treating a new noise as normal
A hum that has grown louder is the one Samsung says to have checked.
Breville's lab figure and LG's support-page range share no method, the usual snag in comparing decibel ratings. The Combi Wave's 56.4 dBA is the only model-specific cooking figure here to hold against how quiet your kitchen needs to be, and at night it is the beeps and the door that carry through the house.
If the microwave you own has started to thump or rattle, clean and reseat the turntable and check that it is not on an uneven surface before you call for service.
