A warm or hot smartphone charger on a blue background
Phone chargers convert alternating current (AC) to direct current (DC) to charge your phone, which generates heat. It is normal for a phone charger to get warm while in use, but it should never be hot enough that it becomes uncomfortable to hold or touch, or that it begins to melt or become discolored.

If you’ve ever noticed that your iPhone or Android phone charger is warm or hot to the touch after using it, you may be wondering why this is happening and if it’s something to worry about. Here’s what you need to know.

Normally, Electronics Produce Some Heat

Some warmth is normal in any phone charger. Your charger converts AC power from your outlet into DC power for your phone, and it generates heat in the process.

To perform the AC/DC conversion, the charger uses an electrical component called a transformer. Transformers produce heat due to the regular process of conducting electricity and also through eddy currents and other losses, which are a side effect of how transformers work. In general, the more current a transformer provides, the more heat it will produce.

Two phones charging

Under normal circumstances, a phone charger might feel a little warm to the touch, and that’s ok—it is operating as designed. But if it’s more than just warm, or unusually warm suddenly when it hasn’t been warm before, then you might have a problem.

How Hot is Too Hot?

If your charger is hot to the point where its uncomfortable to hold or touch, thats a clear sign that something is wrong. This might be due to a malfunction inside the charger itself or a problem with the connection between the charger and the outlet. High quality, authentic chargers have protection circuitry that will automatically shut down the charger if something goes wrong. But this circuit could malfunction, or you could be using a low-quality or counterfeit charger.

If your charger is uncomfortably hot, unplug it from the outlet and look for any visible signs of dirt or obstructions on the prongs that plug into the wall outlet. Also, check to make sure the charging port on your phone is clean, and inspect the USB port on the charger itself (if it has one) for signs of dirt or lint build-up.

Once the port is clean, try again, and if it still gets warm, use a different cable to see if the problem persists. Even so, there are some cases where you don’t want to take any chances with trying different cables, which we’ll cover below.

When Does a Hot Charger Become a Fire Hazard?

A hot, melting phone charger that is smoking

If you see any of these warning signs in your charger or charging cable, discontinue using the charger or cable immediately and replace it. If you have a faulty charger, you could try contacting customer support of the manufacturer to get a replacement.

  • Visible signs of melting in the charger plastic or charger cable.
  • An unusual smell coming from the charger, such as the smell of smoke or melting plastic.
  • Scorch marks (black or brown burn marks) on the charger, cable, or the outlet the charger is plugged into.
  • A sudden amount of heat that is new or unusual.
  • Fraying, cracks, or physical damage to the cable or charger.

Also, remember to charge your phone far away from anything flammable or combustible. That goes for any charger, even one that is working well.

Stick With High Quality, Name-Brand Chargers

As we briefly mentioned above, one reason you might have a hot phone charger is because it is a low quality or counterfeit part. These parts do not comply with safety standards and regulations that keep us safe.

Currently, it’s a well-known industry issue that online vendors such as Amazon.com and AliExpress sell many counterfeit and potentially hazardous electronic products. This includes wireless, wired, and USB phone chargers. If you purchased a charger that is malfunctioning, seek a refund, and consider buying a new charger directly from the manufacturer of your phone, such as Apple or Samsung.

The Best Phone Chargers of 2023

TECKNET 65W Three-Port Charger
Best Overall Charger
TECKNET 65W Three-Port Charger
Apple 20W Power Adapter
Best iPhone/iPad Charger
Apple 20W Power Adapter
Amazon Basics 100W Four-Port GaN Wall Charger
Best Wall Charger
Amazon Basics 100W Four-Port GaN Wall Charger
Anker PowerWave 10W Qi-Certified Charger
Best Wireless Charger
Anker PowerWave 10W Qi-Certified Charger
Best Car Charger
Techsmarter 11-Port Charging Station
Best Charging Station
Techsmarter 11-Port Charging Station

If you do purchase a third-party charger from Amazon, buy only trusted name-brand products from vendors such as Anker, or consult our buying guide for advice. A recent analysis showed that around 42% of Amazon reviews are fake, so you can’t trust those alone. Good luck, and stay safe out there!

RELATED: I Called Out a Counterfeit Item on Amazon. Then They Banned Me.

Profile Photo for Benj Edwards Benj Edwards
Benj Edwards is a former Associate Editor for How-To Geek. Now, he is an AI and Machine Learning Reporter for Ars Technica. For over 15 years, he has written about technology and tech history for sites such as The Atlantic, Fast Company, PCMag, PCWorld, Macworld, Ars Technica, and Wired. In 2005, he created Vintage Computing and Gaming, a blog devoted to tech history. He also created The Culture of Tech podcast and regularly contributes to the Retronauts retrogaming podcast.
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