It's normal for an iPhone to get slightly warm while charging, but excessive heat can damage your internal hardware and shorten battery life. Here are the top 5 reasons why this happens.
Using Non-MFi Certified Chargers
Cheap, third-party cables and adapters often lack the voltage regulation chips required to protect your iPhone's battery.
Fast Charging Stress
Using a 20W or higher power adapter generates significant heat during the first 0-50% of the charge cycle. This is expected but should be monitored.
Heavy Processing While Charging
Gaming (like PUBG or Genshin Impact) or exporting 4K videos while plugged in puts double the stress on the processor and battery.
Trapped Heat in Phone Cases
Thick rubber or leather cases act as insulation, preventing the iPhone's metal body from dissipating heat into the air.
Software Background Activity
If your iPhone is indexing files after an iOS update, it will work much harder during charging, leading to increased temperatures.