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01Is a phone charger making noise dangerous?
A phone charger making noise is usually fine if it's a faint, steady, high-pitched whine. That's coil whine: tiny parts inside vibrating as the charger switches power on and off thousands of times a second. It becomes a problem when the sound is crackling or popping, or comes with heat or a smell.
| What you hear | What it usually is | What to do |
|---|---|---|
| Faint, high-pitched whine | Coil whine | Fine to keep using |
| Whine that changes pitch as the phone charges | Coil whine responding to load | Fine to keep using |
| Louder whine with nothing plugged in | Charger idling in a low-power mode | Unplug it from the wall when not in use |
| Low hum or buzz | Vibrating parts, or a loose fit in the outlet | Try another outlet; replace if it persists |
| Crackling, popping, sizzling or arcing | Failing component or poor contact | Unplug now and replace it |
| Any noise plus heat, smell or scorch marks | Overheating fault | Stop using it immediately |
02Why chargers whine at all
Every modern phone charger is a switch-mode power supply. Instead of one heavy transformer, it chops the incoming power on and off very rapidly, then smooths it into the low DC voltage your phone needs. That's why today's chargers are small and light.
The switching makes small coils and some ceramic capacitors physically flex. Normally that happens far above the range of human hearing. But when the load is light (your phone is nearly full, or nothing is connected) many chargers drop into a power-saving burst mode that switches in pulses, and those pulses can land in the audible range. That's why the whine often gets louder at night, right when the phone hits 100%, and in a quiet bedroom.
Two chargers of the same model can sound different, and younger ears pick up high frequencies that older ears don't. If one person in the house hears it and another doesn't, that's normal.
03How to quiet a whining charger
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Try a different outlet
A loose, worn outlet can make a charger buzz and adds resistance, which also means heat. If the noise drops in another socket, the outlet is the issue.
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Unplug it when nothing is attached
Idle chargers are often the noisiest. It also saves a little standby power.
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Swap the cable
A damaged cable can make the charger hunt for a stable output. Try a known-good cable and see if the pitch changes.
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Move it away from your head
Use a longer cable so the charger sits behind the nightstand rather than next to your pillow. Distance does more than you'd think for a high-pitched sound.
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Try a different charger
If one charger whines and another doesn't, it's that unit's components. It's safe, but you're allowed to be annoyed by it. Replacing it is reasonable.
One thing that won't help: wrapping the charger in tape or stuffing it behind a cushion to muffle it. Chargers need air around them to shed heat, and covering one trades a small annoyance for a real risk.
04When to stop using it
Wall chargers hold mains voltage inside, and some parts can stay charged after unplugging. Never try to repair one. A charger that crackles or smells goes in electronics recycling.
Also check what's plugged into it. A swollen phone battery or a damaged phone port can make a charger behave oddly. If the phone itself is hot or the screen is lifting, stop charging and have the phone checked. Our page on phone overheating while charging covers that side.
05Cheap chargers, fake chargers and noise
Coil whine shows up in good chargers too, so noise alone doesn't mean a charger is fake. What cheap counterfeits skimp on is insulation, spacing between high- and low-voltage parts, and proper temperature protection. Noise plus heat from a no-name or suspiciously cheap charger is the combination to take seriously.
Look for a recognized safety mark such as UL or ETL on chargers sold in the US, a real brand name, and printed output ratings. Our guide on how to spot a fake charger lists the giveaways. If you're replacing one anyway, a GaN charger is smaller and usually runs cooler for the same wattage; see GaN vs regular chargers.
Pick the wattage your phone can use. Any charger can whine faintly; heat, smell and crackling are what should never happen.
06Wireless chargers and stands that buzz
Wireless pads have their own coil, and that coil can hum faintly while it searches for or powers a phone. Some charging stands also have small cooling fans that whir. A brief buzz each time you set the phone down is the pad checking for a device. A constant buzz paired with a blinking light usually means it's struggling with alignment, metal or a weak adapter; see wireless charger blinking.
Questions people ask
Why does my phone charger make a high-pitched noise?
It's almost always coil whine. Parts inside the charger vibrate as it switches power on and off rapidly. It tends to be loudest when the phone is nearly full or nothing is plugged in. It's harmless if there's no heat, smell or crackling.
Is it safe to use a buzzing phone charger?
A faint, steady whine is safe. Crackling, popping, sizzling, a burning smell, or a charger that's too hot to hold is not. Unplug it and replace it.
Why does my charger make noise when nothing is plugged in?
With no load, many chargers drop into a power-saving burst mode, and the pulses can be audible. It's normal. Unplugging the charger from the wall when you're not using it stops the noise.
Can a noisy charger damage my phone?
Coil whine on its own won't. The phone controls how much power it accepts. A charger that's failing, crackling or overheating could deliver unstable power, which is why those should be replaced.
Why does my charger buzz only in certain outlets?
A worn or loose outlet can make the plug vibrate and connect poorly, which causes buzzing and heat. If the noise only happens in one outlet, stop using that outlet and have it checked.