A warm charger is usually fine, but there's a real difference between warm and hot
Your charger getting warm during use is normal. Chargers convert electricity from your wall outlet into the right voltage and current for your device, and that conversion always produces some heat — the same way a light bulb gets warm. You should expect the charger block itself to feel noticeably warm to the touch, especially if you're charging a larger device like a laptop or if the charger has been plugged in for a while.
A charger that's too hot to hold comfortably for more than a few seconds, or one that's hot enough that you don't want to touch it at all, is a sign something is wrong. So is a charger that smells like burning plastic, makes a buzzing or crackling sound, or has visible damage like scorch marks or melted plastic. Those are the situations where you should unplug it immediately and stop using it.
Key Takeaways
- Chargers naturally produce heat during normal operation, and feeling warm to the touch is expected behavior.
- A charger that's too hot to hold comfortably, smells like burning plastic, or makes unusual sounds needs to be unplugged and replaced.
- Damage to the charger cable, using a charger designed for a different device, or a fault inside the charger itself are the main reasons a charger overheats dangerously.
- Leaving a charger plugged in when not charging does produce some heat, but modern chargers are designed to handle this safely.
Why chargers get warm in the first place
Every charger contains a transformer and circuitry that converts the alternating current (AC) from your wall outlet into the direct current (DC) your device needs. That conversion process is not perfectly efficient — some energy is lost as heat. A charger that converts power for a phone might lose 10 to 15 percent of the energy as heat. A charger for a laptop, which draws much more power, can lose 20 to 30 percent.
The amount of heat also depends on how much power your device is actually drawing. A phone charging at full speed will make the charger warmer than a phone that's nearly full and charging slowly. If you're using your phone while it charges, the charger has to work harder and will get warmer. A laptop charger will run hotter when you're using the laptop than when it's just sitting idle.
The difference between warm and dangerously hot
A charger that feels warm — around the temperature of a cup of tea that's still hot but drinkable — is normal. You should be able to hold it in your hand for 10 or 20 seconds without discomfort. If you can't hold it for more than a second or two, or if it's hot enough that you instinctively pull your hand away, the charger is running too hot.
Dangerous heat usually comes with other warning signs. A charger that's overheating often smells like burning plastic or rubber. You might hear a buzzing, crackling, or humming sound that's louder than the quiet hum a normal charger makes. The plastic casing might be discolored, soft, or visibly melted. Any of these signs means you should unplug the charger immediately and not use it again.
The risk of an overheating charger is that it can damage itself internally, fail suddenly, or in rare cases start a fire. A charger that fails can also damage your device or cause an electrical shock. It's not worth the risk to keep using one that shows these signs.
What causes a charger to overheat
The most common cause is damage to the cable or the charger block itself. If the cable is bent sharply, kinked, or has been stepped on, the wires inside can be damaged. That damage creates resistance, which generates extra heat. Look along the entire length of the cable, especially near where it connects to the charger block and where it connects to your device. If you see cracks in the rubber coating, exposed wires, or areas where the cable feels stiff or damaged, that's the problem.
Using the wrong charger for your device is another common cause. If you use a charger designed for a different device — especially one that supplies more power than your device is designed to handle — the charger has to work harder and will overheat. Always use the charger that came with your device, or a replacement charger rated for the same voltage and amperage. The voltage and amperage are printed on the charger block itself.
A fault inside the charger itself is less common but does happen. If the internal circuitry is damaged or defective, the charger can't regulate power properly and will overheat. This usually happens with very old chargers, chargers that have been dropped or exposed to water, or chargers from manufacturers with poor quality control.
How to keep your charger from overheating
Keep the charger in a location with good air circulation. Don't wrap the cable tightly around the charger block, and don't stuff the charger into a pocket, bag, or under a pillow while it's plugged in. Heat needs somewhere to go, and blocking airflow makes the charger work harder. If you're charging a laptop, don't use it on a bed or couch where the charger can sink into soft material — use it on a hard, flat surface.
Avoid bending or kinking the cable, especially near the connectors. If you need to wrap up the cable, coil it loosely rather than wrapping it tightly. If the cable gets damaged, replace the charger rather than trying to repair it with tape or other fixes.
Use the charger that came with your device, or buy a replacement from the device manufacturer or a reputable third-party maker. Cheap, off-brand chargers often have poor internal design and are more likely to overheat. If you need a new charger, check the voltage and amperage printed on the original charger and match those numbers exactly.
What to do if your charger is overheating
Unplug it immediately. Don't try to use it again, and don't try to fix it. A charger that's overheating is a safety risk, and there's no safe way to repair one yourself.
If the charger is still under warranty, contact the device manufacturer. Most manufacturers will replace a defective charger for free within the first year. If it's out of warranty or you bought it from a third party, you'll need to buy a replacement. Look for a charger from the device manufacturer or from a well-known brand that specializes in chargers — Anker, Belkin, and similar companies make reliable third-party chargers that are less expensive than manufacturer chargers but still safe.
If the charger caught fire, melted significantly, or caused visible damage to your device, stop using the device as well and contact the manufacturer. There may be internal damage you can't see.
Is it safe to leave a charger plugged in?
Leaving a charger plugged into the wall when your device isn't connected to it does produce some heat — the charger is still converting power even when it's not delivering it to a device. Modern chargers are designed to handle this safely, and the amount of heat is usually very small. You won't notice it if you touch the charger.
That said, there's no benefit to leaving a charger plugged in when you're not using it. It wastes a small amount of electricity and produces unnecessary heat. If you want to reduce heat and save power, unplug the charger when you're not actively charging a device. This is especially true for laptop chargers, which draw more power and produce more heat than phone chargers.
Frequently Asked Questions
Is it normal for my phone charger to get hot?
Yes. A charger that feels warm to the touch is normal and expected. If you can hold it comfortably in your hand for 10 to 20 seconds, it's fine. If it's too hot to hold, or if it smells like burning plastic, unplug it and get a replacement.
Can a hot charger damage my phone?
A charger that's warm during normal operation won't damage your phone. A charger that's dangerously hot can damage the charging port or the battery if the heat transfers to your device, but the bigger risk is to the charger itself. An overheating charger can fail suddenly or, in rare cases, catch fire.
Why does my laptop charger get so much hotter than my phone charger?
Laptop chargers deliver much more power than phone chargers — often 60 to 100 watts compared to 5 to 20 watts for a phone. More power means more heat. A hot laptop charger is normal, but it should still be warm rather than painfully hot. If you can't hold it, something is wrong.
Can I use a different charger if mine is overheating?
Only if the replacement charger is rated for your device. Check the voltage and amperage printed on both the original charger and the replacement. They must match exactly. Using a charger with different specs can damage your device or cause the charger to overheat.
What should I do if my charger smells like burning plastic?
Unplug it immediately and don't use it again. A burning smell means the charger is overheating dangerously and could fail or catch fire. Get a replacement charger from the device manufacturer or a reputable third-party maker.