According to Apple’s website, the 12-watt USB power adapter can safely charge the iPhone (iPhone 5 and later) using an iPad charger.
The amount of electricity a phone consumes; Power adapters do not “push” power into the phone.
Is it OK to use iPad and iPhone charger?
Yes, it’s safe to charge your iPhone using an iPad charger.
Also, if you have a 30-watt adapter, the 30-watt adapter compatibility page states that it is compatible with the iPhone 8 and later.
Will an iPhone charge faster with an iPad charger?
If you use an iPad charger to charge your iPhone, your iPhone will charge normally, but once it’s fully charged, it will stop charging because iPhone has battery technology that stops charging once it’s fully charged.
What happens if an iPhone uses an iPad charger?
When you use the iPad charger for your iPhone, you should not see any difference.
It just takes longer.