Do I need special voltage converter for 220 to 120 in Europe or can I use the charge I use in the United States. I know I need a special plug adapter
iPhone 6s
No, iPhone's charger works both on 120 volt and 220 volt.
You will just need a physical adapter to convert the US 2 prong to the UK style outlet.
Do I need a voltage converter for my MacBook Pro
A plug adaptor is all you need, the charger itself can run on any voltage between 100 and 240.
do I need a voltage converter for my MacBook Pro *220 to 120* ?
Your question has been answered, twice.
Same answer. All Apple product chargers are universal and work as indicated on the charger: 100-240V 50-60Hz
All you need is a physical adapter as shown above.
Do I need a voltage converter for travel to Ireland?
